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BackgroundSimultaneous Linear Equations
1. Given [A] =
6000
5400
3210
9326
then [A] is a ______________ matrix.
(A) diagonal
(B) identity
(C) lower triangular
(D) upper triangular
2. A square matrix [A] is lower triangular if
(A) i jaij ,0
(B) jiaij ,0
(C) jiaij ,0
(D) i jaij ,0
3. Given
3.123.113.10
3.113.103.11
3.203.123.12
][ A ,
2011
65
42
][ B
then if
[C] = [A] [B], then
c31= _____________________
(A) -58.2
(B) -37.6
(C) 219.4
(D) 259.4
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4. The following system of equations has ____________ solution(s).
x + y = 2
6x+6y =12
(A) infinite
(B) no
(C) two
(D) unique
5. Consider there are only two computer companies in a country. The companies are named
Dude and Imac. Each year, company Dude keeps 1/5th of its customers, while the rest switch to
Imac. Each year, Imac keeps 1/3rd of its customers, while the rest switch to Dude. If in 2003,
Dude had 1/6 th
of the market and Imac had 5/6 th
of the market, what will be share of Dude
computers when the market becomes stable?
(A) 37/90
(B) 5/11(C) 6/11
(D) 53/90
6. Three kids - Jim, Corey and David receive an inheritance of $2,253,453. The money is put in
three trusts but is not divided equally to begin with. Corey's trust is three times that of David's
because Corey made an A in Dr. Kaw’s class. Each trust is put in an interest generating
investment. The three trusts of Jim, Corey and David pays an interest of 6%, 8%, 11%,
respectively. The total interest of all the three trusts combined at the end of the first year is
$190,740.57. The equations to find the trust money of Jim ( J ), Corey (C ) and David ( D) in a
matrix form is
(A)
57.740,190
0
453,253,2
11.008.006.0
130
111
D
C
J
(B)
57.740,190
0
453,253,2
11.008.006.0
310
111
D
C
J
(C)
57.740,190
0
453,253,2
1186310
111
DC
J
d
057,074,19
0
453,253,2
1186
130
111
D
C
J
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Gaussian Elimination
1. The goal of forward elimination steps in Naïve Gauss elimination method is to reduce the
coefficient matrix to a (an) _____________ matrix.
(A) diagonal
(B) identity
(C) lower triangular
(D) upper triangular
2. Division by zero during forward elimination steps in Naïve Gaussian elimination of the set of
equations [A][X]=[C] implies the coefficient matrix [A] is
(A) invertible
(B) nonsingular
(C) not determinable to be singular or nonsingular
(D) singular
3. Using a computer with four significant digits with chopping, Naïve Gauss elimination solution
to
23.47123.7239.6
12.5823.550030.0
21
21
x x
x x
is
(A) x1 = 26.66; x2 = 1.051
(B) x1 = 8.769; x2 = 1.051
(C) x1 = 8.800; x2 = 1.000
(D) x1 = 8.771; x2 = 1.052
4. Using a computer with four significant digits with chopping, Gaussian elimination with partial
pivoting solution to
23.47123.7239.6
12.5823.550030.0
21
21
x x
x x
is
(A) x1 = 26.66; x2 = 1.051
(B) x1 = 8.769; x2 = 1.051(C) x1 = 8.800; x2 = 1.000
(D) x1 = 8.771; x2 = 1.052
5. At the end of forward elimination steps of Naïve Gauss Elimination method on the following
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equations
0
007.0
0
10887.7
106057.3102857.400
15384.05.615384.05.6
104619.5102857.4104619.5102857.4
00102307.9102857.4 3
4
3
2
1
57
5757
57
c
c
c
c
the resulting equations in the matrix form are given by
4
2
3
3
4
3
2
1
5
575
57
1090336.1
1019530.1
10887.7
10887.7
1062500.5000
579684.09140.2600
104619.5102857.4107688.30
00102307.9102857.4
c
c
c
c
The determinant of the original coefficient matrix is
(A) 0.00(B) 7102857.4
(C) 1910486.5
( D) 20104452 . ANSWER
6. The following data is given for the velocity of the rocket as a function of time. To find the
velocity at t=21 s, you are asked to use a quadratic polynomial, v(t)=at 2+bt+c to
approximate the velocity profile.
t (s) 0 14 15 20 30 35
v(t) m/s 0 227.04 362.78 517.35 602.97 901.67
The correct set of equations that will find a, b and c are
(A)
35517
78362
04227
120400
115225
114176
.
.
.
c
b
a
(B)
97.602
35.517
78.362
130900
120400
115225
c
b
a
ANSWER
(C)
35517
78362
0
120400
115225
100
.
.
c
b
a
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(D)
67.901
97.602
35.517
1351225
130900
120400
c
b
a
LU Decomposition Method
1. LU decomposition method is computationally more efficient than Naïve Gauss elimination for
solving
(A) a single set of simultaneous linear equations
(B) multiple sets of simultaneous linear equations with different coefficient matrices
and same right hand side vectors.
(C) multiple sets of simultaneous linear equations with same coefficient matrix and
different right hand side vectors.
(D) less than ten simultaneous linear equations.
2. The lower triangular matrix [L] in the [L][U] decomposition of matrix given below
33
2322
131211
3231
21
00
0
1
01
001
22128
16810
4525
u
uu
uuu
is
(A)
17333.132000.0
0140000.0
001
ANSWER
(B)
2400.400
400.1460
4525
(C)
0128
0110
001
(D)
15000.132000.0
0140000.0
001
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3. The upper triangular matrix [U] in the [L][U] decomposition of matrix given below
33
2322
131211
3231
21
00
0
1
01
001
22120
1680
4525
u
uu
uuu
is
(A)
17333.132000.0
0140000.0
001
(B)
2400.400
400.1460
4525
(C)
200
1680
4525
ANSWER
(D)
240.400
4000.210
16000.02000.01
4. For a given 2000 2000 matrix [A], assume that it takes about 15 seconds to find the inverse
of [A] by the use of the [L][U] decomposition method, that is, finding the [L][U] once, and then
doing forward substitution and back substitution 2000 times using the 2000 columns of the
identity matrix as the right hand side vector. The approximate time, in seconds, that it will take
to find the inverse if found by repeated use of Naive Gauss Elimination method, that is, doing
forward elimination and back substitution 2000 times by using the 2000 columns of the identity
matrix as the right hand side vector is
(A) 300
(B) 1500
(C) 7500
(D) 30000
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5. The algorithm in solving the set of equations [A][X] = [C], where [A] = [L][U] involves
solving [L][Z] = [C] by forward substitution. The algorithm to solve [L][Z]=[C] is given by
(A) 1111 / l c z
for i from 2 to n do
sum = 0
for j from 1 to i do
sum = sum + jij z l *
end do
z i = (ci – sum) / l ii
end do
(B) 1111 / l c z
for i from 2 to n do
sum = 0
for j from 1 to (i-1) do
sum = sum + jij z l *
end do
z i = (ci – sum) / l ii
end do
(C) 1111 / l c z
for i from 2 to n do
for j from 1 to (i-1) dosum = sum + jij z l *
end do
z i = (ci – sum) / l ii
end do
(D) for i from 2 to n do
sum = 0
for j from 1 to (i-1) do
sum = sum + jij
z l *
end do
z i = (ci – sum) / l ii
end do
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6. To solve boundary value problems, finite difference method is used resulting in simultaneous
linear equations with tri-diagonal coefficient matrices. These are solved using the specialized
[L][U] decomposition method. The set of equations in matrix form with a tri-diagonal
coefficient matrix for
22
2
5.06 x xdx
yd
, 00 y , 012 y ,
using finite difference method with a second order accurate central divided difference method
and a step size of 4h is
(A)
0
0.16
0.16
0
1000
0625.0125.00625.00
00625.0125.00625.0
0001
4
3
2
1
y
y
y
y
(B)
0
0.160.16
0
1000
0625.0125.00625.0000625.0125.00625.0
0001
4
3
2
1
y
y y
y
ANSWER
(C)
0.16
0.16
0
0
0625.0125.00625.00
00625.0125.00625.0
1000
0001
4
3
2
1
y
y
y
y
0.16
0.160
0
0625.0125.00625.00
00625.0125.00625.01000
0001
4
3
2
1
y
y y
y
Gauss-Seidel Method of Solving
1. A square matrix [A]nxn is diagonally dominant if
(A) ,1
n
ji j
ijii aa i = 1, 2, …, n
(B) ,1
n
ji j
ijii aa i = 1, 2, …, n and ,1
n
ji j
ijii aa for any i = 1, 2, …, n
(C) ,1
n
j
ijii aa i = 1, 2, …, n and ,1
n
j
ijii aa for any i = 1, 2, …, n
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(D) ,1
n
j
ijii aa i = 1, 2, …, n
2. Using [ x1 x2 x3] = [1 3 5] as the initial guess, the value of [ x1 x2 x3] after three iterations
in Gauss-Seidel method for
6
52
1172
1513712
3
2
1
x
x x
is
(A) [-2.8333 -1.4333 -1.9727]
(B) [1.4959 -0.90464 -0.84914]
(C) [0.90666 -1.0115 -1.0242]
(D) [1.2148 -0.72060 -0.82451]
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3. To ensure that the following system of equations,
17257
52
61172
321
321
321
x x x
x x x
x x x
converges using Gauss-Seidel Method, one can rewrite the above equations as follows:
(A)
17
5
6
257
121
1172
3
2
1
x
x
x
(B)
6
5
17
1172
121
257
3
2
1
x
x
x
(C)
17
5
6
1172
121
257
3
2
1
x
x
x
(D) The equations cannot be rewritten in a form to ensure convergence.
4. For
2
7
22
1172
151
3712
3
2
1
x
x
x
and using 121321 x x x as the initial guess, the
values of 321 x x x are found at the end of each iteration as
Iteration # x1 x2 x3 1 0.41666 1.1166 0.96818
2 0.93989 1.0183 1.0007
3 0.98908 1.0020 0.99930
4 0.99898 1.0003 1.0000
At what first iteration number would you trust at least 1 significant digit in your solution?
(A) 1(B) 2(C)
3(D) 4
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5. The algorithm for the Gauss-Seidel Method to solve [A] [X] = [C] is given as follows for
using nmax iterations. The initial value of [X] is stored in [X].
(A) Sub Seidel(n, a, x, rhs, nmax)
For k = 1 To nmax
For i = 1 To n
For j = 1 To n
If (i <> j) Then
Sum = Sum + a(i, j) * x(j)
endif
Next j
x(i) = (rhs(i) - Sum) / a(i, i)
Next i
Next k
End Sub
(B) Sub Seidel(n, a, x, rhs, nmax)
For k = 1 To nmax
For i = 1 To n
Sum = 0
For j = 1 To n
If (i <> j) Then
Sum = Sum + a(i, j) * x(j)
endif
Next j
x(i) = (rhs(i) - Sum) / a(i, i)
Next i
Next k
End Sub
(C) Sub Seidel(n, a, x, rhs, nmax)
For k = 1 To nmax
For i = 1 To n
Sum = 0
For j = 1 To nSum = Sum + a(i, j) * x(j)
Next j
x(i) = (rhs(i) - Sum) / a(i, i)
Next i
Next k
End Sub
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(D) Sub Seidel(n, a, x, rhs, nmax)
For k = 1 To nmax
For i = 1 To n
Sum = 0
For j = 1 To n
If (i <> j) Then
Sum = Sum + a(i, j) * x(j)
endif
Next j
x(i) = rhs(i) / a(i, i)
Next i
Next k
End Sub
6. Thermistors measure temperature, have a nonlinear output and are valued for a limited range.
So when a thermistor is manufactured, the manufacturer supplies a resistance vs. temperature
curve. An accurate representation of the curve is generally given by
3
3
2
210 lnln)ln(1
Ra Ra RaaT
where T is temperature in Kelvin, R is resistance in ohms, and 3210 ,,, aaaa are constants of the
calibration curve.
Given the following for a thermistor
R T
ohm C
1101.0
911.3
636.0
451.1
25.113
30.131
40.120
50.128
the value of temperature in C for a measured resistance of 900 ohms most nearly is
(A) 30.002
(B) 30.472
(C) 31.272
(D) 31.445
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Cholesky and LDLT Decomposition
1. For a given set of simultaneous linear equations
][]][[ b x A
where
1105.0
1210
0121
5.0012
][ A and
5.1
5
5
5.0
b
The Cholesky factorized matrix ][U can be computed as
(A)
5590.0000
7217.0155.100
2041.08165.0225.10
3536.007071.0414.1
(B)
5590.0000
7217.0155.100
2041.08165.0225.10
3536.007071.0414.1
ANSWER B
(C)
5590.0000
7217.0155.100
2041.08165.0225.10
3536.007071.0414.1
(D)
5590.0000
7217.0155.100
2041.08165.0225.10
3536.007071.0414.1
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2. For a given set of simultaneous linear equations
][]][[ b x A
where
1105.0
1210
0121
5.0012
][ A and
5.1
5
5
5.0
b
the forward solution vector ][ y can be computed as
(A) 5590.0,877.15,784.38,5363.0 T y
(B) 5590.0,784.38,877.15,5363.0 T y
(C) 5590.0,878.3,5877.1,536.3 T y
(D) 5590.0,5877.1,8784.3,3536.0 T y
ANSWER
3. For a given set of simultaneous linear equations
][]][[ b x A
where
1105.0
1210
0121
5.0012
][ A and
5.1
5
5
5.0
b
The backward solution vector ][ x can be computed as
(A) 1,2,2,1 T x
ANSWER
(B) 1,2,2,1 T x
(C) 1,2,2,1 T x
(D) 1,2,2,1T x
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4. The determinant of
1105.0
1210
0121
5.0012
][ A
most nearly is(A) -5(B) 5(C) -50(D) 1.25
5. Based on the given matrix ][ A , and assuming the reordering algorithm will produce the
following mapping IPERM (new equation #) = {old equation #}, such as
2
4
1
3
4
3
2
1
IPERM ,
the non zero off-diagonal term A(old row 4, old column 1) = 0.5 will move to the
following new location of the new matrix ][ * A
(A) * A (new row 3, new column 1)
(B) * A (new row 1, new column 3)
(C) * A (new row 3, new column 2)
(D) * A (new row 2, new column 2)
6. Based on the given matrix ][ A , and the given reordering mapping
2
4
1
3
4
3
2
1
IPERM ,
the non-zero diagonal term 1)4,4( A will move to the following new location of the
new matrix ][ * A
(A) 1)1,1(* A
(B) 1)2,2(* A
(C) 1)3,3(* A ANSWER
(D) 1)4,4(* A
7. For a given set of simultaneous linear equations, and using LDLT algorithm,
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][]][[ b x A
where
1105.0
1210
0121
5.0012
][ A and
5.0
1
1
2
][b ,
the lower triangular matrix ][ L can be computed as
(A)
1625.01667.025.0
016667.00
0015.0
0001
][ L ANSWER
(B)
1625.01667.025.0
016667.00
0015.0
0001
][ L
(C)
1625.01667.025.0
016667.00
0015.0
0001
][ L
(D)
1625.01667.025.0
016667.00
0015.0
0001
][ L
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8. For a given set of simultaneous linear equations, and using LDLT algorithm,
][]][[ b x A
where
1105.0
1210
0121
5.0012
][ A and
5.0
1
1
2
][b ,
the diagonal matrix ][ D can be computed as:
(A)
3125.0000
03333.100
005.10
0002
][ D
(B)
3125.0000
03333.100
005.10
0002
][ D
(C)
3125.0000
03333.100
005.10
0002
][ D
(D)
3125.0000
03333.100
005.10
0002
][ D ANSWER
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9. For a given set of simultaneous linear equations, and using LDLT algorithm,
][]][[ b x A
where
1105.0
1210
0121
5.0012
][ A and
5.0
1
1
2
][b ,
the forward solution for the unknown vector ][ z in ][]][[ b z L can be computed as
(A) 625.0,1,0,2T z
(B) 625.0,1,0,2T z ANSWER
(C) 625.0,1,0,2 T z
(D) 625.0,1,0,2 T z
10. For a given set of simultaneous linear equations, and using LDLT algorithm,
][]][[ b x A
where
1105.0
1210
0121
5.0012
][ A and
5.0
1
1
2
][b ,
the diagonal scaling solution for the unknown vector ][ y in ][]][[ z y D can be computed
as:(A) 2,75.0,0,1T
y
(B) 2,75.0,0,1 T y
(C) 2,75.0,0,1 T y
(D) 2,75.0,0,1T y ANSWER
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11. For a given set of simultaneous linear equations, and using LDLT algorithm,
][]][[ b x A
where
1105.0
1210
0121
5.0012
][ A and
5.0
1
1
2
][b ,
the backward solution for the original unknown vector ][ x , in ][][][ y x L T , can be
computed as
(A) 2,2,1,1T x ANSWER
(B) 1,2,1,2T x
(C) 1,2,1,1T x
(D)
1,2,2,2T
x
12. Given the following 6 6 matrix ][ A , which is assumed to be SPD:
0
00
0
000
000
Sym
A
where = a nonzero value (given)
0 = a zero value (given)Based on the numerically factorized formulas shown in Equations 6-7 of Chapter 04.11,or even more helpful information as indicated in Figure 1 of Chapter 04.11, and given
* = a nonzero value (computed, at the same location as the original nonzero value
of ][ A )
0 = a zero value F = a nonzero fill-in-term (computed)
and
0)6,5(
)6,5(
A
F U
the symbolically factorized upper-triangular matrix can be obtained as
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(A)
F
U 00
0
000
000
ANSWER
(B)
F
F
U 00
0
000
000
(C)
F
F F
U 00
0000
000
D
F
F F
F
U 00
0
000
000
Background on Interpolation
1. The number of polynomials that can go through two fixed data points 11, y x and 22, y x
is(D) 0(E) 1(F) 2(G) Infinite D ANSWER
2. A unique polynomial of degree __________________ passes through 1n data points.
(A) 1n
(B) 1n or less
(C) n
(D) n or less
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3. The following function(s) can be used for interpolation:(A) polynomial(B) exponential(C) trigonometric
(D) all of the above
4. Polynomials are the most commonly used functions for interpolation because they areeasy to
(A) evaluate(B) differentiate(C) integrate
(D) evaluate, differentiate and integrate
5. Given 1n data points nnnn y x y x y x y x ,,,,......,,,, 111100 , assume you pass a
function )( x f through all the data points. If now the value of the function )( x f is
required to be found outside the range of the given x -data, the procedure is called
(A) extrapolation (B) interpolation(C) guessing(D) regression
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6. Given three data points (1,6), (3,28), and (10, 231), it is found that the function
132 2 x x y passes through the three data points. Your estimate of y at 2 x is
most nearly(A) 6(B) 15
(C) 17(D) 28
Direct Method of Interpolation
1. A unique polynomial of degree ________________ passes through 1n data points.
(E) 1n
(F) 1n or less
(G) n
(H) n or less
2. The following data of the velocity of a body is given as a function of time.
Time (s) 0 15 18 22 24
Velocity (m/s) 22 24 37 25 123
The velocity in m/s at s16 using linear polynomial interpolation is most nearly(I) 27.867
(J) 28.333(K) 30.429(L) 43.000
3. The following data of the velocity of a body is given as a function of time.
Time (s) 0 15 18 22 24Velocity (m/s) 22 24 37 25 123
The velocity in m/s at s16 using quadratic polynomial interpolation is most nearly(M) 27.867(N) 28.333
(O) 30.429(P) 43.000
4. The following data of the velocity of a body is given as a function of time.
Time (s) 0 15 18 22 24
Velocity (m/s) 22 24 37 25 123
Using quadratic interpolation, the interpolant ,352367.349667.8 2 t t t v 2418 t
approximates the velocity of the body. From this information, the time in seconds at
which the velocity of the body is 35 m/s during the above time interval of s18t to
s24t is(Q) 18.667(R) 20.850
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(S) 22.200
(T) 22.294
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5. The following data of the velocity of a body is given as a function of time.
Time (s) 0 15 18 22 24
Velocity (m/s) 22 24 37 25 123
One of the interpolant approximations for the velocity from the above data is given as
,352367.3496667.8)( 2 t t t v 2418 t
Using the above interpolant, the distance in meters covered by the body between s19t and s22t is most nearly
(U) 10.337
(V) 88.500(W) 93.000(X) 168.00
6. The following data of the velocity of a body is given as a function of time.
Time (s) 0 15 18 22 24
Velocity (m/s) 22 24 37 25 123
If you were going to use quadratic interpolation to find the value of the velocity at
9.14t seconds, what three data points of time would you choose for interpolation?
A) 0, 15, 18B) 15, 18, 22C) 0, 15, 22D) 0, 18, 24
Newton’s Divided Difference Polynomial Method1. If a polynomial of degree n has n 1 zeros, then the polynomial is(A) oscillatory
(B) zero everywhere(C) quadratic(D) not defined
2. The following x, y data is given.
x 15 18 22 y 24 37 25
The Newton’s divided difference second order polynomial for the above data is given by
181515)( 2102 x xb xbb x f
The value of b1 is most nearly(A) – 1.0480(B) 0.14333
(C) 4.3333(D) 24.000
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3. The polynomial that passes through the following x, y data
x 18 22 24 y ? 25 123
is given by
,323775.324125.8 2 x x 2418 x
The corresponding polynomial using Newton’s divided difference polynomial is given by 221818)( 2102 x xb xbb x f
The value of b2 is most nearly(A) 0.25000
(B) 8.1250
(C) 24.000(D) not obtainable with the information given
4. Velocity vs. time data for a body is approximated by a second order Newton’sdivided difference polynomial as
,15205540.020622.390 t t t bt v 2010 t
The acceleration in 2 m/s at t 15 is(A) 0.5540(B) 39.622
(C) 36.852(D) not obtainable with the given information
5. The path that a robot is following on a x y plane is found by interpolating thefollowing four data points as
900.3605.9257.21524.0 23
x x x x y
The length of the path from x 2 to x 7 is(A)
2222225.57655.45.55.7625.45.75.7
(B)
(C) dx x x 7
2
22 )605.9514.44572.0(1 ANSWER
D) dx x x 7
2
22 )605.9514.44572.0(1
x 2 4.5 5.5 7 y 7.5 7.5 6 5
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6. The following data of the velocity of a body is given as a function of time.
Time (s) 0 15 18 22 24
Velocity (m/s) 22 24 37 25 123
If you were going to use quadratic interpolation to find the value of the velocity at
t 14.9 seconds, the three data points of time you would choose for interpolation are
(A) 0, 15, 18(B) 15, 18, 22(C) 0, 15, 22(D) 0, 18, 24
Lagrange Method of Interpolation
1. A unique polynomial of degree ______________ passes through 1n data points.
A) 1n
B) n
C)n or lessD) 1n or less
2. Given the two points b f ba f a ,,, , the linear Lagrange polynomial x f 1 that passes
through these two points is given by
A ) b f ba
a xa f
ba
b x x f
1
B ) b f ab
xa f
ab
x x f
1
C)
ab
ab
a f b f a f x f
1
D) b f ab
a xa f
ba
b x x f
1 ANSWER
3. The Lagrange polynomial that passes through the 3 data points is given by
x 15 18 22 y 24 37 25
253724 2102 x L x L x L x f
The value of x L1 at 16 x is most nearly
A) – 0.071430
B) 0.50000
C) 0.57143D) 4.3333
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4. The following data of the velocity of a body is given as a function of time.
Time ( s ) 10 15 18 22 24
Velocity ( sm ) 22 24 37 25 123
A quadratic Lagrange interpolant is found using three data points, 15t , 18 and 22.From this information, at what of the times given in seconds is the velocity of the body
m/s26 during the time interval of 15t to 22t seconds.A) 20.173
B) 21.858
C) 21.667D) 22.020
5. The path that a robot is following on a y x, plane is found by interpolating four data
points as
x 2 4.5 5.5 7 y 7.5 7.5 6 5
9000.36048.92571.215238.0 23 x x x x y
The length of the path from 2 x to 7 x is
(A) 2222225.57655.45.55.7625.45.75.7
(B) dx x x x 7
2
223 )9000.36048.92571.215238.0(1
(C)
dx x x
7
2
22
)6048.95142.445714.0(1 ANSWER
(D) dx x x x 7
2
23 )9000.36048.92571.215238.0(
6. The following data of the velocity of a body is given as a function of time.
Time (s) 0 15 18 22 24
Velocity (m/s) 22 24 37 25 123
If you were going to use quadratic interpolation to find the value of the velocity at
9.14t seconds, what three data points of time would you choose for interpolation?
A) 0, 15, 18 B) 15, 18, 22
C) 0, 15, 22D) 0, 18, 24
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Background
1. Physically, integrating b
a
dx x f )( means finding the
A) area under the curve from a to b
B) area to the left of point a
C) area to the right of point b
D) area above the curve from a to b
2. The mean value of a function )( x f from a to b is given by
A) 2
)()( b f a f
B) 4
)(2
2)( b f ba
f a f
C) b
a
dx x f )(
D) ab
dx x f
b
a
)(
ANSWER
3. The exact value of 2.2
2.0
dx xe x is most nearly
A) 7.8036
B) 11.807C) 14.034
D) 19.611
4. 2
2.0
)( dx x f for
2.10,)( x x x f
4.22.1,2 x x
is most nearlyA) 1.9800
B) 2.6640C) 2.7907
D) 4.7520
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5. The area of a circle of radius a can be found by the following integral
A) a
dx xa0
22
B) 2
0
22 dx xa ANSWER
C) a
dx xa0
224
D) a
dx xa0
22
6. Velocity distribution of a fluid flow through a pipe varies along the radius and is given by
)(r v . The flow rate through the pipe of radius a is given by
A) 2)( aav ANSWER
B) 2
2
)()0( aavv
C) a
dr r v0
)(
D) a
rdr r v0
)(2
Trapezoidal Rule
1. The two-segment trapezoidal rule of integration is exact for integrating at most ________order polynomials.
A) firstB) second
C) thirdD) fourth
2. The value of 2.2
2.0
dx xe x by using the one-segment trapezoidal rule is most nearly
A) 11.672
B) 11.807C) 20.099D) 24.119
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3. The value of 2.2
2.0
dx xe x by using the three-segment trapezoidal rule is most nearly
A) 11.672B) 11.807
C) 12.811
D) 14.633
4. The velocity of a body is given by51,2)( t t t v
145,35 2 t t
where t is given in seconds, and v is given in m/s. Use the two-segment trapezoidal rule
to find the distance in meters covered by the body from 2t to 9t seconds.A) 935.00
B) 1039.7
C) 1260.9
D) 5048.95. The shaded area shows a plot of land available for sale. The units of measurement are in
meters. Your best estimate of the area of the land in 2m is most nearlyA) 2500
B) 4775
C) 5250D) 6000
6. The following data of the velocity of a body is given as a function of time.
Time ( s ) 0 15 18 22 24
Velocity ( sm ) 22 24 37 25 123
The distance in meters covered by the body from s12t to s18t calculated usingthe trapezoidal rule with unequal segments is
60
75
45
25
10060
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A) 162.90B) 166.00C) 181.70D) 436.50
Simpson’s 1/3 Rule
1. The highest order of polynomial integrand for which Simpson’s 1/3 rule of integration isexact is
A) firstB) second
C) third
D) fourth
2. The value of 2.2
2.0
dxe x by using 2-segment Simpson’s 1/3 rule most nearly is
A) 7.8036
B) 7.8423C) 8.4433D) 10.246
3. The value of 2.2
2.0
dxe x by using 4-segment Simpson’s 1/3 rule most nearly is
A) 7.8036
B) 7.8062
C) 7.8423D) 7.9655
4. The velocity of a body is given by51,2)( t t t v
145,35 2 t t
where t is given in seconds, and v is given in m/s. Using two-segment Simpson’s 1/3
rule, the distance in meters covered by the body from 2t to 9t seconds most nearlyis
A) 949.33B) 1039.7
C) 1200.5D) 1442.0
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5. The value of 19
3
)( dx x f by using 2-segment Simpson’s 1/3 r ule is estimated as 702.039.
The estimate of the same integral using 4-segment Simpson’s 1/3 rule most nearly is
A) 1521172
3
8039.702 f f f
B) 15211723
8
2
039.702 f f f ANSWER
C) 152723
8039.702 f f
D) 152723
8
2
039.702 f f
6. The following data of the velocity of a body is given as a function of time.
Time (s) 4 7 10 15
Velocity (m/s) 22 24 37 46The best estimate of the distance in meters covered by the body from 4t to 15t using combined Simpson’s 1/3 rule and the trapezoidal rule would be
A) 354.70
B) 362.50
C) 368.00D) 378.80
Romberg Rule
1.
If n I is the value of integral
b
a dx x f using n -segment trapezoidal rule, a better estimate
of the integral can be found using Richardson’s extrapolation as
A) 15
22
nnn
I I I
B) 3
22
nnn
I I I
ANSWER
C) n I 2
D) n
nnn
I
I I I
2
22
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2. The estimate of an integral of 19
3
dx x f is given as 1860.9 using 1-segment trapezoidal
rule. Given 27.207 f , 125.4511 f , and 23.8214 f , the value of the integral
using 2-segment trapezoidal rule would most nearly be
A) 787.32B) 1072.0
C) 1144.9
D) 1291.5
3. The value of an integral b
a
dx x f given using 1, 2, and 4 segments trapezoidal rule is
given as 5.3460, 2.7708, and 1.7536, respectively. The best estimate of the integral youcan find using Romberg integration is most nearly
A) 1.3355
B) 1.3813
C) 1.4145D) 1.9124
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4. Without using the formula for one-segment trapezoidal rule for estimating b
a
dx x f the
true error, t E can be found directly as well as exactly by using the formula
12
3
ab E t " f , ba
for
A) xe x f
B) x x x f 33
C) 35 2 x x f ANSWER
D) xe x x f 25
5. For b
a
dx x f , the true error, t E in one-segment trapezoidal rule is given by
12
3ab
E t
" f , ba
The value of for the integral dxe x
2.7
5.2
2.03 is most nearly
A) 2.7998B) 4.8500
C) 4.9601
D) 5.0327
6. Given the velocity vs. time data for a bodyt (s) 2 4 6 8 10 25
m/s 0.166 0.55115 1.8299 6.0755 20.172 8137.5
The best estimate for distance covered in meters between 2t s and 10t s by usingRomberg rule based on trapezoidal rule results would be
A) 33.456B) 36.877C) 37.251D) 81.350
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Gauss Quadrature Rule
1. 10
5
)( dx x f is exactly
A)
1
1
)5.75.2( dx x f
B)
1
1
)5.75.2(5.2 dx x f ANSWER
C)
1
1
)55(5 dx x f
D)
1
1
)()5.75.2(5 dx x f x
2. For a definite integral of any third order polynomial, the two-point Gauss quadrature rulewill give the same results as the
A) 1-segment trapezoidal ruleB) 2-segment trapezoidal rule
C) 3-segment trapezoidal ruleD) Simpson’s 1/3 rule
3. The value of 2.2
2.0
dx xe x by using the two-point Gauss quadrature rule is most nearly
A) 11.672B) 11.807C) 12.811D) 14.633
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4. A scientist uses the one-point Gauss quadrature rule based on getting exact results of
integration for functions 1)( x f and x . The one-point Gauss quadrature rule
approximation for b
a
dx x f )( is
A) )()(2
b f a f ab
B)
2)( ba f ab ANSWER
C)
23
1
223
1
22
abab f
abab f
ab
D) )()( a f ab
5. A scientist develops an approximate formula for integration as
b
a
x f cdx x f ),()( 11 where b xa 1
The values of 1c and 1 x are found by assuming that the formula is exact for functions of
the form 2
10 xa xa . The resulting formula would therefore be exact for integrating
A) 2)( x f
B) 2532)( x x x f
C) 25)( x x f ANSWER
D) x x f 32)(
6. You are asked to estimate the water flow rate in a pipe of radiusm2
at a remote arealocation with a harsh environment. You already know that velocity varies along the
radial location, but you do not know how it varies. The flow rate Q is given by
2
0
2 rVdr Q
To save money, you are allowed to put only two velocity probes (these probes sendthe data to the central office in New York, NY via satellite) in the pipe. Radial
location, r is measured from the center of the pipe, that is 0r is the center of the pipe and m2r is the pipe radius. The radial locations you would suggest for thetwo velocity probes for the most accurate calculation of the flow rate are
A) 0, 2B) 1, 2C) 0, 1
D) 0.42, 1.58
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