SUCCESS ONEHSC · 2020-04-17 · 463 2018 HIGHER SCHOOL CERTIFICATE—EXAMINATION PAPER P P ISN 8 1...
Transcript of SUCCESS ONEHSC · 2020-04-17 · 463 2018 HIGHER SCHOOL CERTIFICATE—EXAMINATION PAPER P P ISN 8 1...
PLUSTopic index of
past HSC questions
Past HSC papers and worked answers
1994–2018
SUCCESS ONE ®
HSC*
MATHEMATICS EXTENSION 1
Free-to-download Sample Tests with answers
462
2018 HIGHER SCHOOL CERTIFICATE—EXAMINATION PAPER
NSW Education Standards Authority
2018 HIGHER SCHOOL CERTIFICATE EXAMINATION
Mathematics Extension 1 General Instructions
• Reading time – 5 minutes • Working time – 2 hours • Write using black pen • Calculators approved by NESA may be used • A reference sheet is provided at the back of this paper • In Questions 11–14, show relevant mathematical reasoning
and/ or calculations
Total marks: 70
Section I – 10 marks (pages 2–5) • Attempt Questions 1–10 • Allow about 15 minutes for this section
Section II – 60 marks (pages 6–13) • Attempt Questions 11–14 • Allow about 1 hour and 45 minutes for this section
1260
2018 HSC Mathematics Extension 1 Examination Paper
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
463
2018 HIGHER SCHOOL CERTIFICATE—EXAMINATION PAPER
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
464
2018 HIGHER SCHOOL CERTIFICATE—EXAMINATION PAPER
4 The diagram shows the graph of y = a(x + b)(x + c)(x + d)2.
O
−6
x1−1−2
y
What are possible values of a, b, c and d ?
A. a = −6, b = −2, c = −1, d = 1
B. a = −6, b = 2, c = 1, d = −1
C. a = −3, b = −2, c = −1, d = 1
D. a = −3, b = 2, c = 1, d = −1
5 The diagram shows the number of penguins, P(t), on an island at time t.
t
P
3000
1500
– 3 –
Which equation best represents this graph?
A. P(t) = 1500 + 1500e−kt
B. P(t) = 3000 − 1500e−kt
C. P(t) = 3000 + 1500e−kt
D. P(t) = 4500 − 1500e−kt
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
465
2018 HIGHER SCHOOL CERTIFICATE—EXAMINATION PAPER
– 4 –
6 The diagram shows the graph of y = â ( x ). The equation â ( x ) = 0 has a solution at x = w .
O x
y
a b c d w
y = â (x )
Newton’s method can be used to give an approximation close to the solution x = w.
Which initial approximation, x1, will give the second approximation that is closest to the solution x = w?
A. x1 = a
B. x = b1
C. x1 = c
D. x1 = d
7 The velocity of a particle, in metres per second, is given by v = x2 + 2, where x is its displacement in metres from the origin.
What is the acceleration of the particle at x = 1?
A. 2 m s−2
B. 3 m s−2
C. 6 m s−2
D. 12 m s−2
©
Pas
cal P
ress
ISB
N 9
78 1
741
25 6
95 6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
466
2018 HIGHER SCHOOL CERTIFICATE—EXAMINATION PAPER
– 5 –
8 Six men and six women are to be seated at a round table.
In how many different ways can they be seated if men and women alternate?
A. 5! 5!
B. 5! 6!
C. 2! 5! 5!
D. 2! 5! 6!
9 1
Which of the following is a general solution of the equation sin 2x = − ?2
pA. x = np + (−1)n
12
np pB. x = + (−1)n
2 12
n+1 pC. x = np + (−1)
12
np pD. x = + (−1)n+1
2 12
10 A particle is moving in simple harmonic motion. The displacement of the particle is x and
its velocity, v, is given by the equation v2 = n2 ( 2kx − x2 ), where n and k are constants.
The particle is initially at x = k.
Which function, in terms of time t, could represent the motion of the particle?
A. x = k cos (nt)
B. x = k sin (nt) + k
C. x = 2k cos (nt) − k
D. x = 2k sin (nt) + k
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
467
2018 HIGHER SCHOOL CERTIFICATE—EXAMINATION PAPER
Question 11 continues on the following page
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
468
2018 HIGHER SCHOOL CERTIFICATE—EXAMINATION PAPER ©
Pas
cal P
ress
ISB
N 9
78 1
741
25 6
95 6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
469
2018 HIGHER SCHOOL CERTIFICATE—EXAMINATION PAPER
Question 12 continues on the following page
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
470
2018 HIGHER SCHOOL CERTIFICATE—EXAMINATION PAPER ©
Pas
cal P
ress
ISB
N 9
78 1
741
25 6
95 6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
471
2018 HIGHER SCHOOL CERTIFICATE—EXAMINATION PAPER
Question 13 continues on the following page ©
Pas
cal P
ress
ISB
N 9
78 1
741
25 6
95 6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
472
2018 HIGHER SCHOOL CERTIFICATE—EXAMINATION PAPER
Question 13 (continued)
(c) An object is projected from the origin with an initial velocity of V at an angle q to the horizontal. The equations of motion of the object are
x(t) = Vt cosq gt2
y(t) = Vt sinq − . (Do NOT prove these.) 2
(i) Show that when the object is projected at an angle q, the horizontal range V 2
is sin 2q . g
2
p (ii) Show that when the object is projected at an angle − q, the horizontal
2 2 V
range is also sin 2q . g
1
(iii) The object is projected with initial velocity V to reach a horizontal distance d, which is less than the maximum possible horizontal range. There are two angles at which the object can be projected in order to travel that horizontal distance before landing.
p Let these angles be a and b, where b = − a.
2
Let ha be the maximum height reached by the object when projected at the angle a to the horizontal.
Let hb be the maximum height reached by the object when projected at the angle b to the horizontal.
3
ab
V V
hb
ha
d
h + hShow that the average of the two heights, a b, depends only
2on V and g.
End of Question 13
– 11 –
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
473
2018 HIGHER SCHOOL CERTIFICATE—EXAMINATION PAPER
Question 14 continues on the following page
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
474
2018 HIGHER SCHOOL CERTIFICATE—EXAMINATION PAPER
© 2018 NSW Education Standards Authority
– 13 –
Question 14 (continued)
(c) In triangle ABC, BC is perpendicular to AC. Side BC has length a, side AC has length b and side AB has length c. A quadrant of a circle of radius x, centred at C, is constructed. The arc meets side BC at E. It touches the side AB at D, and meets side AC at F. The interval CD is perpendicular to AB.
C
BD
F
c
x
xx1
a
b
E
A
C
B
F
G
D
H
A. . .
(i) Show that rABC and rACD are similar.
1
ab(ii) Show that x = .
c1
From F, a line perpendicular to AC is drawn to meet AB at G, forming the right‑angled triangle GFA. A new quadrant is constructed in triangle GFA touching side AB at H. The process is then repeated indefinitely.
C
BD
F
c
x
xx1
a
b
E
A
C
B
F
G
D
H
A. . .
pab2
(iii) Show that the limiting sum of the areas of all the quadrants is .4(2c − a)
4
p 2c − a(iv) Hence, or otherwise, show that < .
2 b 1
End of paper © P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
475
2018 Higher School CertificateWorked Answers
(Total 10 marks)
1. B 2. A 3. A 4. D 5. A 6. C 7. C 8. B 9. D 10. B
1. P(x) = 2x3 + 6x2 – 7x – 10
αβγ = da
= 102
= 5
α + β + γ = ba
= 62
= –3
So αβγ (α + β + γ) = 5 × –3
= –15
Answer B
2. y = 3x has gradient m1 = 3
y = 5x has gradient m2 = 5
Now tan θ = m1 m2
1+m1m2
= 3 5
1+ 3 5
= 18
Answer A
3. limx 0
sin3xcos3x12x
= limx 0
sin6x24x
= 14limx 0
sin6x6x
= 14
Answer A
4. There are single roots at –2 and –1 and a double root at 1.
So possible values of b and c are 2 and 1 and a possible value of d is –1.
So y = a(x + 2)(x + 1)(x – 1)2
When x = 0, y = –6
–6 = a(0 + 2)(0 + 1)(0 – 1)2
–6 = 2a
a = –3
Answer D
5. P(0) = 3000
Now 1500e0 = 1500
So possible equations are A and D.
As t → ∞ , 1500e–kt → 0
So the equation that best represents the graph is P(t) = 1500 + 1500e–kt.
Answer A
6. The tangent at c cuts the x-axis at the closest point to w, so the initial approximation x1 = c, will give the second approximation that is closest to x = w.
O x
y
a b c d w
y = ƒ (x )
Answer C
7. v = x2 + 2
Now a = vdvdx
= (x2 + 2) × 2x
= 2x3 + 4x
When x = 1,
dvdt
= 2 × 13 + 4 × 1
= 6
The acceleration of the particle is 6 m s–2.
Answer C
8. The men can sit in (6 – 1)! or 5! ways.
For each of those the women can sit in 6! ways.
Number of ways = 5! 6!
Answer B
Section ISection I
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
476
2018 HIGHER SCHOOL CERTIFICATE—WORKED ANSWERS
9. sin 2x = 12
2x = nπ + (–1)n sin 1 12
= nπ + (–1)n 6
= nπ + (–1)n+1 6
x = n2
+ (–1)n+1 12
Answer D
10. v2 = n2(2kx – x2)
= n2(k2 – k2 + 2kx – x2)
= n2(k2 – (x2 – 2kx + k2))
= n2(k2 – (x – k)2)
So x – k = k cos (nt + α)
x = k cos (nt + α) + k
But x = k when t = 0.
So x = k sin (nt) + k could represent the motion.
Answer B
QUESTION 11
(a) P(x) = x3 – 2x2 – 5x + 6
(i) P(1) = 13 – 2 × 12 – 5 × 1 + 6 = 0 ∴ x = 1 is a zero of P(x).
(1 mark)
(ii)
x 1 x3 2x2 5x+ 6x2 x 6
x3 x2
x2 5xx2 + x
6x+ 66x+ 6
0
So P(x) = (x – 1)(x2 – x – 6) = (x – 1)(x + 2)(x – 3) ∴ the other zeros are x = –2 and x = 3.
(2 marks)
(b) log25 + log2(x – 2) = 3
log2(5x – 10) = 3
∴ 5x – 10 = 23
5x – 10 = 8
5x = 18
x = 3.6
(2 marks)
Section II
(c) 3 sin x + cos x ≡ R sin (x + α) Now R sin (x + α) = R sin x cos α + R cos x sin α ∴ R cos α = 3 and R sin α = 1
RsinRcos
= 13
tan α = 13
α = 6
02
R cos 6
= 3
R × 3
2 = 3
R = 2
∴ 3 sin x + cos x ≡ 2 sin x+6
(2 marks)
(d) The products of the intercepts of secants from an external point are equal.
∴ x(x + 2) = 3 × (3 + 5)
x2 + 2x = 24
x2 + 2x – 24 = 0
(x – 4)(x + 6) = 0
x = 4 or x = –6
But x > 0
∴ x = 4
(2 marks)
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
477
2018 HIGHER SCHOOL CERTIFICATE—WORKED ANSWERS
(e) f(x) = 1
4x 1
(i) Now 4x – 1 ≠ 0 4x ≠ 1
x ≠ 14
Domain is all real x except x = 14
.
(1 mark)
(ii) f(x) < 1
If x < 14
, the denominator is negative and so f(x) is also negative and hence less than 1.
If x > 14
,
1
4x 1 < 1
1 < 4x – 1
2 < 4x
12
< x
So f(x) < 1 when x < 14
and when x > 12
.
(2 marks)
(f) Let u = 1 – x x = 1 – u dx = –du
When x = 0, u = 1When x = –3, u = 4
∴ x
1 x dx
3
0
= 1 uu �
du4
1
= u12 u
12 du
1
4
= u12
12
u32
32 1
4
= 2 u2u u
31
4
= 2 42 4 4
32 1
2 1 13
= –223
(3 marks)
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
478
2018 HIGHER SCHOOL CERTIFICATE—WORKED ANSWERS
QUESTION 12
(a) cos 2θ = cos2θ – sin2θ = 2 cos2θ – 1
So cos2θ = 12
(cos 2θ + 1)
cos2 3x( ) dx = 12
cos 6x+ 1( )dx
= 1
12 sin 6x +
x2
+ C
(2 marks)
(b) (i) sin θ = h20
h = 20 sin θ
dhd
= 20 cos θ
(1 mark)
(ii) ddt
= 1.5
dhdt
= dhd �
ddt
= 20 cos θ × 1.5 = 30 cos θ When h = 15,
sin θ = 1520
= 34
cos θ = 134
2
(θ is acute, so cos θ > 0)
So dhdt
= 30 134
2
= 19.843 1348… = 19.8 (1 d.p.)The top of the carriage is rising at 19.8 m per minute, correct to one decimal place.
(2 marks)
(c) (i) f(x) = sin–1x + cos–1x
f'(x) = 1
1 x2 + 1
1 x2
= 0
(1 mark)
20 m h
θ
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
479
2018 HIGHER SCHOOL CERTIFICATE—WORKED ANSWERS
(ii) f'(x) = 0
∴ f(x) is constant.
When x = 0,
f(x) = sin–10 + cos–10 = 0 +
2 =
2 ∴ f(x) =
2 for all x in the domain.
∴ sin–1x + cos–1x = 2
(1 mark)
(iii) sin–1x and cos–1x have domain –1 ≤ x ≤ 1.
x1
y = sin–1x + cos–1x
y
π2
–1 0
(1 mark)
(d) P(finishes in 8 h) = 0.75
∴ P(does not finish in 8 h) = 0.25
P(at least 10 finish in 8 h)
= P(10 finish) + P(11 finish) + P(12 finish)
= 1210
(0.75)10(0.25)2 + 1211
(0.75)11(0.25) + 1212
(0.75)12
= 66 34
10 14
2
+ 12 34
11 14
+ 34
12
= 66 310 +12 311 + 312
412
= 311 22 +12 + 3( )
412
= 37 311
412
(2 marks)
(e) (i) The tangent at P has equation y = px – ap2.
The gradient of the tangent is m1 = p.
At A, y = 0
∴ px – ap2 = 0
px = ap2
x = ap (p ≠ 0)
A(ap, 0), S(0, a)
m = y2 y1
x2 x1
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
480
2018 HIGHER SCHOOL CERTIFICATE—WORKED ANSWERS
m2 = a 0
0 ap
= 1p
Now m1m2 = p × 1p
= –1 ∴ AS is perpendicular to AP. ∴ ∠PAS = 90°
(2 marks)
(ii) Similarly, BS is perpendicular to BQ. So ∠TBS = 90°
O B
QST
A x
y
P
x2 = 4ay
So ∠TAS = ∠TBS Angles in same segment standing on
the same arc are equal. ∴ S, B, A and T are concyclic points.
(1 mark)
(iii) An angle in a semicircle = 90°. So ST is a diameter of the circle
through S, B, A and T. S(0, a), T(a(p + q), apq)
d = x2 x1( )2 + y2 y1( )2
= a p+q( ) 0( )2+ apq a( )2
= a2 p+q( )2 +a2 pq 1( )2
= a p2 + 2pq+q2 + p2q2 2pq+1
= a p2q2 + p2 +q2 +1
= a p2 q2 +1( )+1 q2 +1( )
= a p2 +1( ) q2 +1( )(2 marks)
QUESTION 13
(a) To prove 2 – 6 + 18 – 54 + … + 2(–3)n–1 = 1 3( )n
2.
When n = 1, LHS = 2(–3)1–1
= 2
RHS = 1 3( )1
2 = 2 \ it is true for n = 1. Assume true for n = k
i.e. assume 2 – 6 + 18 – 54 + … + 2(–3)k–1 = 1 3( )k
2 We want to prove that it is true for n = k + 1.
i.e. 2 – 6 + 18 – 54 + … + 2(–3)k = 1 3( )k+1
2
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
481
2018 HIGHER SCHOOL CERTIFICATE—WORKED ANSWERS
LHS = 2 – 6 + 18 – 54 + … + 2(–3)k – 1 + 2(–3)k
= 1 3( )k
2 + 2(–3)k
= 1 3( )k + 4 3( )k
2
= 1+ 3 3( )k
2
= 1 3( )k+1
2 = RHS So, if true for n = k, it is also true for n = k + 1. It is true for n = 1, so it is true for n = 1 + 1 = 2. It is true for n = 2, so it is true for n = 2 + 1 = 3. And so on. By the process of induction it is true for all integers n ≥ 1.
(3 marks)
(b) (i) f(x) = x
x2 +1, x ≥ 1
Range of f(x) is 0 < y ≤ 12
.
So the domain of f –1(x) is 0 < x ≤ 12
.
Range of f –1(x) is y ≥ 1.
(2 marks)
(ii)
x
y = ƒ –1x
y
2
0
( , 1)1
(1 mark)
(iii) y = x
x2 +1
Inverse function:
x = y
y2 +1
xy2 + x = y
xy2 – y + x = 0
y = b± b2 4ac
2a
= 1( )± 1( )2 4 x x
2x
= 1± 1 4x2
2x
But, y ≥ 1
∴ y = 1+ 1 4x2
2x(3 marks)
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
482
2018 HIGHER SCHOOL CERTIFICATE—WORKED ANSWERS
(c) (i) y = Vt sin θ – gt 2
2
When y = 0,
Vt sin θ – gt 2
2 = 0
t 2V sin θ –
gt22
= 0
t = 0 or V sin θ – gt2
= 0
gt = 2V sin θ
t = 2V sin
g
Now x = Vt cos θ
When t = 2V sin
g,
x = 2V 2 sin cos
g
= V 2 sin2
g
So the horizontal range of the projectile
is V 2
g sin 2θ.
(2 marks)
(ii) When the object is projected at 2
:
x = V 2
g sin 2
2
= V 2
g sin (π – 2θ)
= V 2
g sin 2θ
So the horizontal range of the projectile is
also V 2
g sin 2θ.
(1 mark)
(iii) When projected at angle α:
y = Vt sin α – gt 2
2
y = V sin α – gt
Maximum height occurs when y = 0
i.e 0 = V sin α – gt
gt = V sin α
t = V sing
When t = V sing
,
hα = V 2 sin2
g gV sing
2
2
= V 2 sin2
g V 2 sin2
2g
= V 2 sin2
2g
Similarly, when projected at angle β:
hβ = V 2 sin2
2g
Now sin2β = sin2 2
= cos2α
So hβ = V 2 cos2
2g
h + h
2 =
V 2 sin2
2g+V 2 cos2
2g2
= V 2 sin2 + cos2( )
4g
= V 2
4g
So the average of the two heights depends only on V and g.
(3 marks)
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
483
2018 HIGHER SCHOOL CERTIFICATE—WORKED ANSWERS
QUESTION 14
(a) ∠DAB + ∠ABC + ∠BCD + ∠CDA = 360° (angle sum of quadrilateral) So 2α + 2β + 2γ + 2δ = 360° α + β + γ + δ = 180° ∠BPQ = ∠PAB + ∠ABP (ext. ∠ of ∆) = α + β ∴ ∠SPQ = 180° – (α + β) (angles in st. line) ∠DRS = ∠RCD + ∠CDR (ext. ∠ of ∆) = γ + δ ∴ ∠QRS = 180° – (γ + δ) (angles in st. line) ∠SPQ + ∠QRS = 180° – (α + β) + 180° – (γ + δ) = 360° – (α + β + γ + δ) = 360° – 180° = 180°∴ PQRS is a cyclic quadrilateral because the opposite angles are supplementary.
(3 marks)
(b) (i) (1 + (1 + x))n
= n0
+ n1
(1 + x) + n2
(1 + x)2 + n3
(1 + x)3 +…. + nn
(1 + x)n
= n0
+ n1
10
+11x +
n2
20
+21x+
22x2
+ n3
30
+31x+
32x2 +
33x3 +…. +
nn
n0
+n1x+…+
nnxn
So the coefficient of xr will be nr
rr
+n
r+1r+1r
+n
r+ 2r+ 2r
+…+nn
nr
(2 + x)n = n0
2n + n1
2n–1x + n2
2n–2x2 + n3
2n–3x3 +…. + nn
xn
The coefficient of xr will be nr
2n – r.
But 1 + (1 + x) = 2 + x.
So the coefficient of xr in both expansions must be equal.
∴ nr
rr
+n
r+1r+1r
+n
r+ 2r+ 2r
+…+nn
nr
= nr
2n – r
(3 marks)
(ii) Selector A chooses at least 4 from 23. So the number of ways selector A can choose a group is
234
+235
+236
+237
+…+2323
If selector A chooses a group of 4 then selector B must choose 4 from 4. If selector A chooses a group of 5 then selector B must choose 4 from 5. So for each of the
groups of 5 that selector A has chosen there are 54
possible selections of the group of 4.
If selector A chooses a group of 6 then selector B must choose 4 from 6. So, for each of the
groups of 6 that selector A has chosen there are 64
possible selections of the group of 4, and
so on.
A
B C
D
Q
P R
S
α
γγ
δ δ
ββ
α
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
484
2018 HIGHER SCHOOL CERTIFICATE—WORKED ANSWERS
So the number of ways for the selection process is given by:
234
44
+235
54
+236
64
+237
74
+…+2323
234
Using the result from part (i) the selection process could be carried out in 234
223 – 4 ways.
So the selection process could be carried out in 234
219 or 4 642 570 240 ways.
(2 marks)
(c) (i) In ∆ABC, ∆ACD ∠BAC = ∠CAD (common angle) ∠ACB = ∠ADC (both 90°) ∴ ∆ABC ||| ∆ACD (equiangular)
(1 mark)
(ii) CDBC
= ACAB
(corresponding sides similar triangles)
xa
= bc
x = abc
(1 mark)
(iii) Total area of all quadrants
= 14πx2 +
14πx1
2 + 14πx2
2 + …
= 4
(x2 + x12 + x2
2 + …)
Now ∆AHF ||| ∆ADC (equiangular)
So HFDC
= AFAC
x1
x = b xb
= b
abc
b
= 1 – ac
xx1
C
B
F
G
D
H
A. . .
ac
x b – xb
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.
485
2018 HIGHER SCHOOL CERTIFICATE—WORKED ANSWERS
Now as the same process of forming quadrants continues each subsequent triangle will be similar to all the previous ones and the ratios of the radii will be the same.
So x2
x1
= 1 – ac
and x3
x2
= 1 – ac
and so on.
x1
x
2
= x2x1
2
= x3
x2
2
…
So x2 + x12 + x2
2 + … is a geometric series.
r = 1ac
2
= 1 – 2ac
+a2
c2
= 1 – 2ac a2
c2
= 1 – a 2c a( )
c2
As 0 < r < 1, x2 + x12 + x2
2 + … is an infinite geometric series.
Limiting sum = x2
1 1a 2c a( )
c2
=
abc
2
a 2c a( )c2
= a2b2
c2
c2
a 2c a( )
= ab2
2c a
Limiting sum of all areas = 4
× ab2
2c a
= ab2
4 2c a( )(4 marks)
(iv) Limiting sum of all areas must be less than the area of the triangle.
So ab2
4 2c a( ) <
12
ab
b
2 2c a( ) < 1 (a > 0, b > 0)
2
<2c ab
< 2
<2c ab
(c > a so 2c – a > 0)
(1 mark)
© P
asca
l Pre
ss IS
BN
978
1 7
4125
695
6
iv Exce l S U C C E S S O N E H S C • M A T H E M A T I C S E X T E N S I O N 1
PAST HSC EXAMINATION PAPERSThe past HSC Examination papers contained in this publication have been reproduced under licence from the NSW Education Standards Authority (NESA) in whom copyright is vested.
NESA takes no responsibility for errors in the reproduction of past HSC Examination papers contained in this publication.
NESA was the first publisher of each examination paper in the year indicated on the first page of each examination paper.
HSC Examination papers in 3 Unit Mathematics 1994–2000 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 1994–2000.
HSC Examination papers in Mathematics Extension 1 2001–2018 © NSW Education Standards Authority for and on behalf of the Crown in right of the State of New South Wales 2001–2018.
WORKED ANSWERSThe worked answers contained in this publication are examples of answers which the authors believe would score full marks. They are not necessarily ideal or model answers, nor are they the only answers which would score full marks. They are not endorsed by NESA.
Worked answers for the 1994–2003 HSC Examination papers were written by José Carreno.
Worked answers for the 2004–2008 HSC Examination papers were written by Barbara D’Angelo and Megan McKeown.
Worked answers for the 2009 HSC Examination paper were written by Barbara D’Angelo.
Worked answers for the 2010–2018 HSC Examination papers were written by Lyn Baker.
THE HSC MATHEMATICS EXTENSION 1 EXAMINATIONFrom 2001, HSC Mathematics Extension 1 has been the new name for the former HSC 3 Unit Mathematics course.
Since 2012 the HSC Mathematics Extension 1 Examination paper has consisted of two sections. Section I has 10 objective-response questions worth 10 marks in total. Section II has four questions worth 15 marks each. Each of these four questions consists of a number of parts where working should be shown.
There is reading time of 5 minutes and working time of 2 hours.
Students should note that marks are shown for each part of each question and should allocate their time accordingly.