Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of...

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MCR3U – Unit 1: Rational Expressions Lesson 1 Date:___________ Learning goal: I can add, subtract, and multiply polynomials. Expanding and Simplifying Polynomials COLLECTING LIKE TERMS Recall: only like terms can be collected through addition and subtraction. a) 5 3 + 6 2 + 3 b) 4 3 + 7 3 6 + 7 c) 3 ! + 5 ! + 6 ! 5 ! MULTIPLYING MONOMIALS Recall: multiple coefficients with coefficients and variables with variables. a)(2)(4) b) (2 ! )(3 ! ) c) 3 ! (2)(5 ! ) DISTRIBUTION Recall: multiple the term in front of the bracket to each term inside the bracket. a) 4( + 3) b) 4(2 ! 5 + 7) c) 2 4 5 7 ( 2) d 3 ! 2 ! 4 + 7 7(3 ! + 4 ! 7) MULTIPLYING BINOMIALS Recall: multiply each term in the first bracket by each term in the second bracket (FOIL rule). a) + 3 ( 4) b) 5 (3 ) c) 2 1 (3 5) d) 5 2 !

Transcript of Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of...

Page 1: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

MCR3U–Unit1:RationalExpressions–Lesson1 Date:___________Learninggoal:Icanadd,subtract,andmultiplypolynomials.

ExpandingandSimplifyingPolynomials COLLECTINGLIKETERMS

Recall:onlyliketermscanbecollectedthroughadditionandsubtraction.

a) 5𝑥 − 3𝑦 + 6 − 2𝑦 + 3𝑥 b) 4 − 3𝑥 + 7 − 3𝑦 − 6𝑦 + 7𝑥 c)3𝑎!𝑏 + 5𝑎𝑏! + 6𝑎𝑏! − 5𝑎𝑏!

MULTIPLYINGMONOMIALS

Recall:multiplecoefficientswithcoefficientsandvariableswithvariables.

a)(−2𝑥)(4𝑥) b)(2𝑏!)(−3𝑏!) c)3𝑎!(2𝑎)(5𝑎!)

DISTRIBUTION

Recall:multipletheterminfrontofthebrackettoeachterminsidethebracket.

a)4(𝑥 + 3) b)4𝑥(2𝑥! − 5𝑥 + 7)

c)2 𝑥 − 4 − 5 𝑥 − 7 − (𝑥 − 2) d3𝑏! 2𝑏! − 4𝑏 + 7 − 7𝑏(3𝑏! + 4𝑏! − 7𝑏)

MULTIPLYINGBINOMIALS

Recall:multiplyeachterminthefirstbracketbyeachterminthesecondbracket(FOILrule).

a) 𝑥 + 3 (𝑥 − 4) b) 𝑥 − 5 (3 − 𝑥) c) 2𝑥 − 1 (3𝑥 − 5) d) 5𝑥 − 2!

Page 2: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

Simplify 2𝑥 + 1)(3𝑥 − 4)(𝑥 − 2 intwodifferentways.

MethodOne

2𝑥 + 1)(3𝑥 − 4)(𝑥 − 2

MethodTwo

2𝑥 + 1)(3𝑥 − 4)(𝑥 − 2

CONSOLIDATION

Simplifyingeachofthefollowing.

a)(3𝑥 − 2)(4𝑥 − 1)2 b)(2𝑥 + 5)𝟐 − 2 3𝑥 + 7 + (𝑥 − 2)𝟐

c)4 − 2 𝑥 − 3 2𝑥 − 1 d)5 − 2 𝑥 − 3 ! + 2 𝑥 + 4 𝑥 − 1 − 7

HW:ExpandandSimplifyWorksheet

Page 3: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

ExpandandSimplifyWorksheetPleasecompleteallworkonaseparatepage.1. 2. 3.

4. 5. 6.

7. 8. 9.

10. 11.

12. 13.

14. 15.

Answers

1. 2. 3.

4. 5. 6.

7. 8. 9.

10. 11.

12. 13.

14. 15.

( )( )33 −+ xx ( )( )82 −+ xx ( )( )105 ++ xx

( )( )132 −+ xx ( )( )832 −+ xx ( )( )2312 ++ xx

( )( )323 −+ xx ( ) ( )1215 2 −+ xx ( )( ) 6105 +++ xx

( )( )21252 +− xx ( )( )( )14323 −−+ xxx

( ) ( )2522523 ++− xx 3x + 2( )2 −3 x + 4( )+ x − 4( )2

( )( ) ( )7531253 +−−+ xxx ( ) ( ) ( )22 1523213 +−+− xxx

( )( )33 −+ xx ( )( )82 −+ xx ( )( )105 ++ xx92 −= x 1662 −−= xx 50152 ++= xx

( )( )132 −+ xx ( )( )832 −+ xx ( )( )2312 ++ xx32 2 −+= xx 1623 2 −−= xx 276 2 ++= xx

( )( )323 −+ xx ( ) ( )1215 2 −+ xx ( )( ) 6105 +++ xx932 2 −+= xx

( )( )185501211025

23

2

−−−=

−++=

xxxxxx

56152 ++= xx

( )( )21252 +− xx ( )( )( )14323 −−+ xxx( )( )51812814452

23

2

−−−=

++−=

xxxxxx ( )( )

821591869

23

2

+−−=

−−−=

xxxxxx

( ) ( )2522523 ++− xx ( ) ( ) ( )22 44323 −++−+ xxx( )35468

2520421562

2

++=

+++−=

xxxxx

8101681234129

2

22

++=

+−+−−++=

xxxxxxx

( )( ) ( )7531253 +−−+ xxx ( ) ( ) ( )22 1523213 +−+− xxx

26862115576

2

2

−−=

−−−+=

xxxxx

( )( ) ( )

136351822050316151811025232169

23

223

22

+−−=

−−−+−+=

++−++−=

xxxxxxxxxxxxx

Page 4: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

MCR3U–Unit1:RationalExpressions–Lesson2 Date:___________Learninggoal:Icanidentifywhentocommonfactorbeforefactoringsimpleandcomplextrinomials.

Factoring COMMONFACTORING

Recall:wearelookingforfactorsthatarecommontoallterms.

a)2𝑥 + 50 b) 12𝑥!𝑦 − 18𝑥!𝑦! + 24𝑥!𝑦! c) 3𝑥 𝑥 − 1 − 2(𝑥 − 1)

Note:whenfactoringyoumustALWAYScommonfactorfirstifpossible.

‘SIMPLE’TRINOMIALS

Asimpletrinomialisoneintheform𝒂𝒙 𝟐 + 𝒃𝒙 + 𝒄,where𝒂 = 𝟏.Ifitisfactorable,asimpletrinomialcanbeexpressedasaproductoftwobinomials.Theconstanttermsofthebinomialsareintegersthatmultiplytogive“c”andaddtogive“b”. a)𝑣! + 2𝑣 − 15 b)−2𝑡! + 26𝑡 − 84 c)−𝑛! + 4𝑛 + 32

DIFFERENCEOFSQUARES

Aspecialcircumstancewithtwoterms,wherethefirsttermandthelasttermarebothsquares,andthetwotermsaresubtracted(𝑏 = 0).

a)𝑥! − 𝑦! b) 25𝑡! − 64 c) 𝑐! − 36𝑑!" d)16𝑥! − 81𝑦!

Page 5: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

‘COMPLEX’TRINOMIALS

Acomplextrinomialisoneintheform𝒂𝒙 𝟐 + 𝒃𝒙 + 𝒄,where𝒂 ≠ 𝟏.Wearenolongerlookingfortwonumbersthataddtobandmultiplytoc.

a)2𝑘! + 3𝑘 + 1 b)18𝑥! + 33𝑥 + 12 c)27𝑦! − 6𝑦 − 56

d) 2𝑝! − 𝑝! − 28 e) 6𝑥! − 8𝑥! + 2𝑥! f)21𝑎! + 32𝑎𝑏 − 5𝑏!

Canalltrinomialsbefactored?

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Factoring–TheDecisionTreeTheDifferentTypesoffactoring:

1. CommonFactoring2. DifferenceofSquares(∆2–!2)3. “Simple”Trinomial(ax2+bx+c,a=1)4. “Tricky”Trinomial(ax2+bx+c,a≠1)

Strategyforfactoring:

HW:FactoringWorksheet

START

CommonFactoringTakethegreatestcommonfactoroutofeachtermintheexpression.

e.g.3x2–12x

Howmanytermsarethere?

2terms

3terms

DifferenceofSquares∆2 –!2 = (∆ +!)(∆ –!)

e.g.16x2–49

ax2+bx+c

a=1

a≠1

“Simple”TrinomialFind2integersthatmultiplyto“c”and

addto“b”

e.g.x2+3x–10

“Tricky”TrinomialFind2integersthatmultiplyto“(a)(c)”andaddto“b”.Replacethe“b”termwithtwotermswhosecoefficientsarethose2

integers,thenfactorbygrouping.

e.g.2x2–x–6

Canwefactoranyofthefactorsagain?If“yes”,RESTART!

ax2-c

Page 7: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

FactoringWorksheetFactoreachofthefollowingonaseparatepieceofpaper.1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. b2–36 20. m2–25 21. 81n2–12122. x2–4x+4 23. 9a2+48a+64 24. 32c2–48c+1825. 26. 27. 28. 29. 30. 31. x2+3xy−28y2 32. 25x4−121y2 33. x6−8x3−20 34. 4x4−4x2−15 35. 6x4−8x6+2x3 36. 21a2+32ab−5b2 37. x2−y2 38. x4−y4 39. 2x4−2x2 40. x2y+17xy−60y 41. 2x³y–8xy³ 42. 9x2+64y2

Bonus:Factor:x2(a+b)+10x(a+b)+16(a+b) Answers1.5x2(4x3–11) 2.4x(3+2x3) 3.4x3(1–3x2)(1+3x2)4.6x2y(3+5y4)5.–7xy2(x2y–4)6.9x2y(3+y–7x2y2)7.(x–7)(x–8) 8.(x+10)(x+5) 9.(x–6)(x+5) 10.(x+9)(x–4)11.(x–9)(x–1)12.(x–2)(x–3)13.(x+2)(4x–5)14.(x+2)(3x+1) 15.(x+3)(2x–1)16.(a+2)(3a–2)17.((y–1)(4y+3)18.(a+b)(5a–7b)19.(b–6)(b+6)20.(m+5)(m–5) 21.(9n+11)(9n–11)22.(x–2)2 23.(3a+8)2 24.2(4c–3)225.2(x+5)(x+8)26.–3(x2+x–24) 27.4(x–8)(x+2)28.2(x+3)(x+7)29.2(2x+5)230.9(x–3)231.(x+7y)(x−4y)32.(5x2−11y)(5x2+11y)33.(x3−10)(x3+2)34.(2x2−5)(2x2+3)35.2x3(3x−4x3+1)

36.(7a−b)(3a+5b)37.(x+y)(x−y)38. ( )( )( )2 2x y x y x y− + + 39.2x2(x+1)(x−1)

40.y(x+20)(x−3)41.2xy(x–2y)(x+2y)42.Cannotbefactoredbonus.(a+b)(x+8)(x+2)

25 5520 xx − 4812 xx + 73 364 xx −

522 3018 yxyx + 233 287 xyyx +− 34323 63927 yxyxyx −+

56152 +− xx 50152 ++ xx 2 30x x− −

3652 −+ xx 9102 +− xx 2 5 6x x− +

1034 2 −+ xx 23 7 2x x+ + 22 5 3x x+ −

3a2 + 4a− 4 24 3y y− − 2 25 2 7a ab b− −

80262 2 ++ xx 23 3 72x x− − + 64244 2 −− xx

22 20 42x x+ + 28 40 50x x+ + 81549 2 +− xx

Page 8: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

MCR3U–Unit1:RationalExpressions–Lesson3 Date:___________Learninggoal:Icanidentifyrestrictionstosimplifyrationalexpressions.

SimplifyingRationalExpressions WARMUP:Canyousimplifythefollowing? a) !"!

!!!!!"

b)!!!!!!!!

c) !!!!!!

d)!!!!!

!!!!

e) (!!!)(!!!)

(!!!) f)!!!!!!!! g)

!!!!!!! f)

!!!!!!"!!!

ArationalExpressionisafractionwherethe__________________and__________________are

__________________.

RESTRICTIONSWheneveryouareworkingwithalgebraicfractions,itisimportanttodetermineanyvaluesthatmustbeexcluded.Whathappensineachofthefollowingexpressionswhen𝑥 = 3issubstituted? a) !!!

!!! b) !!!

!!!!!!!

Wheneveryouusearationalexpression,youmustidentifyanyvaluesthatmustbeexcluded,theseareknown

asrestrictedvalues.Restrictionsareanyvaluesthatmakethe_____________________________.Itisvery

importantthatyoustaterestrictionsfromthefullyfactoredexpression,beforesimplifying.

Page 9: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

Example1:Foreachrationalexpression,determinetherestrictions. a) !!

!!! b) !!!!

(!!!)(!!!!) c) !!

!!!! d) !!!!

!!!!!!"

SIMPLIFYINGRATIONALEXPRESSIONS

SuccessCriteriaforsimplifyingrationalexpressions

1.

2.

3.

Example2:Simplifyeachrationalexpression.Statetherestrictions.

a)!"!!!!"!!!"

b) !!!!!!!"

!!!!"!!!"

c)!!!!!!

!!!!!! d)

!!!!!"!!"!!

!!!!!!"!!"!!

Page 10: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

MULTIPLESOFNEGATIVEONEWhenyouarefactoringrationalexpressionsyoumustbecarefuloffactorsthatareoffby-1.

ie.!!!!!!

Example3:Simplifyandstateallrestrictions.

a)!!!!!!!"!"!!!

b) !!!!

!!!!!!!!

APPLICATONS

Example4:Anexpressionforcalculatingthedrugdose(inmg)foryoungchildrenis!""!!!!""!!!!""!!"!!!!"!

,where 𝑡istheirageinyears.

a) Determinethedoseforatwo-year-oldchildbeforesimplifyingb) Determinethedoseforatwo-year-oldchildaftersimplifying c) Determinethedoesforathree-year-oldchild

Page 11: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

Example5:Writeanexpressionthatsatisfiesthegivenconditionsineachcase

a) Therestrictionsare-2and5.

b) Therestrictionsare1and-3andtheexpressionis !!!!

insimplestform.

c) Equivalentto!!!!!!

witharestrictionof±4.

d) Equivalentto!!!!!

withadenominatorof12𝑥

e) !!!!!!"!!!!"!!

= !?

HW:Pg353-355#1,3,4,8–14(Ans.Corr9a:− 𝟗𝒙

𝟒𝒚 ,9d:𝒙 ≠ ±𝟓𝒚)

Page 12: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

MCR3U–Unit1:RationalExpressions–Lesson4 Date:___________Learninggoal:Icanmultiplyanddividerationalexpressionswhilestateallrestrictions.

MultiplyingandDividingRationalExpressions WARMUP:Simplifyeachofthefollowing.Staterestrictionswherenecessary.

a)!!× !"!" b)!!

!

!!× !!!

!!" c)(!"

!)÷ (!"

!")

MULTIPLYINGRATIONALEXPRESSIONS

Findingcommonfactorsandsimplifyingisfasterthanmultiplyingnumeratorsanddenominators.

Example1:Multiplyeachrationalexpression.Stateanswerinsimplestform.Identifyandstateallrestrictions a) !!"!!!

!!!!"!!!"× !!!!

!!!!!!!" b)!

!!!"!!!"!!!!!!!"

× !!!!"!!!!!

DIVIDINGRATIONALEXPRESSIONSYoumustbecarefulwhenyoudividerationalexpressionsbecauseyoumustconsiderrestrictionsbeforeandafterreciprocatingthesecondterm.

ie.!!÷ !

!doesnotexistbecausewecannotdivide!

! byzero.

Also,!!÷ !

!doesnotexistbecausewecannotdivide3byzero.

SuccessCriteriaformultiplyingrationalexpressions

1.

2.

3.

4.

Page 13: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

Example2:Divideeachrationalexpression.Stateanswerinsimplestform.Identifyandstateallrestrictions

a) !!!!÷ !!!!!!!"

!! b) !

!!!"!!

÷ !!!!"!!

c) !"!!!!

!!!!!

d) !!!!!"!!!!!!!!!"!

÷ !!!!!!!!

!!!!!!× !!!!!

!!"

HW:Pg359-360#(4-8)ace,17ab

SuccessCriteriafordividingrationalexpressions

1.

2.

3.

4.

5.

Page 14: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

MCR3U–Unit1:RationalExpressions–Lesson5 Date:___________Learninggoal:Icanfindacommondenominatorandadd/subtractrationalexpressions.

AddingandSubtractingRationalExpressions WARMUP:Evaluateeachofthefollowing.

a)!!+ !

! b)!!

!+ !!

!" c)!

!− !

!d)!!

!

!"− !!!

!

Example1:Simplifyeachofthefollowing.Stateanyrestrictions.

a) !

!− !

!!− !

!! b) !

!!!!"+ !

!!!!"

SuccessCriteriaforaddingandsubtractingrationalexpressions

1.

2.

3.

4.

5.

Page 15: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

c) !!!!!!

!!!!!!!− !"!

!!!!" d) !

!!!!!!!− !

!!!!!!!

e) !!!!!!

+ !!!!!!

f)!!!!!!!!

− !!!!!!!!!!

!!!!!!÷ !!!!!"!!!

!!!!"

HW:Pg.370-371#5ace,6ace,7,9aef,19

Page 16: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

MCR3U–Unit1:RationalExpressions–Lesson6 Date:___________Learninggoal:Icanfindacommondenominateandevaluaterationalequations.

SolvingEquationswithRationalExpressions WARMUP:Solveeachofthefollowingusingoppositeoperations.a)3𝑥 − 7 = 14 b) 3𝑥! − 2𝑥 + 5 = 2𝑥! − 3𝑥 + 25 Recall:Wecansolveequationswithfractionsbyusingacommondenominator.Unlikesimplifyingexpressions,whensolvinganequationwehavetheluxuryofbeingabletomultiply(aslongaswemultiplyonbothsides).

Wedon’tneedtomakethedenominatorscommon,sincewecanclearallfractionsbymultiplyingbyacommondenominator.

Example1:Evaluatebyclearingfractions.

a)!!− !!!

!= 4+ !!!!

!

SuccessCriteriaforsolvingrationalexpressions

1.

2.

3.

4.

Page 17: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial

Example3:Solveeachrationalexpression.

a) !!!!

+ !!!!!!!!!

= !!!!

b) !!!!

+ !!!!!

= 5c) !

!!!!!!!"= !

!!!+ !

!!!

HW:Pg.370#11,puzzle132

Page 18: Expanding and Simplifying PolynomialsFactoring – The Decision Tree The Different Types of factoring: 1. Common Factoring 2. Difference of Squares (∆2 –!2) 3. “Simple” Trinomial