ADVANCED SUBSIDIARY GCE 4755/0 MATHEMATICS (MEI) Further Cocepts for Advaced Mathematics (FP) MONDAY JUNE 008 Additioal materials: Aswer Booklet (8 pages) Graph paper MEI Examiatio Formulae ad Tables (MF) Morig Time: hour 0 miutes INSTRUCTIONS TO CANDIDATES Write your ame i capital letters, your Cetre Number ad Cadidate Number i the spaces provided o the Aswer Booklet. Read each questio carefully ad make sure you kow what you have to do before startig your aswer. Aswer all the questios. You are permitted to use a graphical calculator i this paper. Fial aswers should be give to a degree of accuracy appropriate to the cotext. INFORMATION FOR CANDIDATES The umber of marks is give i brackets [ ] at the ed of each questio or part questio. The total umber of marks for this paper is 7. You are advised that a aswer may receive o marks uless you show sufficiet detail of the workig to idicate that a correct method is beig used. This documet cosists of 4 prited pages. OCR 008 [D/0/66] OCR is a exempt Charity [Tur over
Sectio A (6 marks) (i) Write dow the matrix for reflectio i the y-axis. [] (ii) Write dow the matrix for elargemet, scale factor, cetred o the origi. [] (iii) Fidthematrixforreflectioithey-axis, followed by elargemet, scale factor, cetred o the origi. [] Idicate o a sigle Argad diagram (i) the set of poits for which ( + j) =, (ii) the set of poits for which arg( j) =π, (iii) the two poits for which ( + j) = adarg( j) =π. [] Fid the equatio of the lie of ivariat poits uder the trasformatio give by the matrix M = ( ). 4 Fid the values of A, B, C ad D i the idetity x x + A(x ) +(x + Bx + Cx + D). [5] 4 0 5 YouaregivethatA = ( 5) ad B = ( 4 4 7 ). 4 5 7 4 (i) Calculate AB. (ii) Write dow A. [] 6 The roots of the cubic equatio x + x x + = 0areα, β ad γ. Fid the cubic equatio whose roots are α, β ad γ, expressig your aswer i a form with iteger coefficiets. [5] 7 (i) Show that r r + for all itegers r. [] (r )(r + ) (ii) Hece use the method of differeces to fid r= (r )(r + ). [5] OCR 008 4755/0 Ju08
8 A curve has equatio y = x (x )(x + ). Sectio B (6 marks) (i) Write dow the equatios of the three asymptotes. (ii) Determie whether the curve approaches the horizotal asymptote from above or below for (A) large positive values of x, (B) large egative values of x. (iii) Sketch the curve. (iv) Solve the iequality x < 0. (x )(x + ) 9 Two complex umbers, α ad β, aregivebyα = j ad β = + j. α ad β are both roots of a quartic equatio x 4 + Ax + Bx + Cx + D = 0, where A, B, C ad D are real umbers. (i) Write dow the other two roots. [] (ii) Represet these four roots o a Argad diagram. [] (iii) Fid the values of A, B, C ad D. [7] 0 (i) Usig the stadard formulae for r= r= r ad r= r,provethat r (r + ) = ( + )( + )( + ). [5] (ii) Prove the same result by mathematical iductio. [8] OCR 008 4755/0 Ju08
4 Permissio to reproduce items where third-party owed material protected by copyright is icluded has bee sought ad cleared where possible. Every reasoable effort has bee made by the publisher (OCR) to trace copyright holders, but if ay items requirig clearace have uwittigly bee icluded, the publisher will be pleased to make ameds at the earliest possible opportuity. OCR is part of the Cambridge Assessmet Group. Cambridge Assessmet is the brad ame of Uiversity of Cambridge Local Examiatios Sydicate (UCLES), which is itself a departmet of the Uiversity of Cambridge. OCR 008 4755/0 Ju08
4755 Mark Scheme Jue 008 4755 (FP) Further Cocepts for Advaced Mathematics Qu Aswer Sectio A 0 (i) 0 Mark Commet (ii) 0 0 (iii) 0 0 0 = 0 0 0 A [4] Multiplicatio, or other valid method (may be implied) c.a.o. B B Circle, ; cetre + j, ; radius =, Lie parallel to real axis, ; through (0, ), ; correct half lie, - x x = y y x y= x, x+ y = y y = x [7] Poits + j ad 5+ j idicated c.a.o. x x For = y y 4 x x + A( x ) + ( x + Bx + Cx+ D) + + + + + Ax Ax Ax A x Bx Cx D ( A ) x ( B A) x ( A C) x ( D A) + + + + + A=, B= 5, C = 6, D= 4 B4 [5] Attempt to compare coefficiets Oe for each correct value 9
4755 Mark Scheme Jue 008 5(i) 7 0 0 AB = 0 7 0 0 0 7 B Mius each error to miimum of 0 5(ii) A 0 4 4 7 = 7 5 7 4 A [] Use of B c.a.o. 6 w w= x x = w w w + + = 0 A Substitutio. For substitutio x = w give B0 but the follow through for a maximum of marks Substitute ito cubic Correct substitutio 6 OR w + w w+ = α + β + γ = 6 4 0 αβ + αγ + βγ = αβγ = A [5] Mius for each error (icludig = 0 missig), to a miimum of 0 Give full credit for iteger multiple of equatio All three Let ew roots be k, l, m the B k + l+ m = ( α + β + γ) = = A ( αβ αγ βγ ) kl + km + lm = 4 + + = 6= D klm = 8αβγ = 4= A ω + ω 6ω+ 4= 0 C A A A [5] Attempt to use sums ad products of roots of origial equatio to fid sums ad products of roots i related equatio Sums ad products all correct ft their coefficiets; mius oe for each error (icludig = 0 missig), to miimum of 0 Give full credit for iteger multiple of equatio 0
4755 Mark Scheme Jue 008 7(i) ( r )( r+ ) r+ ( r ) ( )( ) r r+ r r+ A [] Attempt at correct method Correct, without fudgig 7(ii) = r r+ r r+ r ( )( ) = r= =... + + + 5 5 8 + = + A A [5] Attempt to use idetity Terms i full (at least two) Attempt at cacellig A if factor of missig, A max if aswer ot i terms of Sectio A Total: 6
4755 Mark Scheme Jue 008 Sectio B 8(i) x =, x =, y = 8(ii) 8(iii) + Large positive x, y (e.g. cosider x = 00 ) Large egative x, y (e.g. cosider x = 00 ) Evidece of method required Curve Cetral ad RH braches correct Asymptotes correct ad labelled LH brach correct, with clear miimum y = 8(iv) < x < x 0 B B max if ay iclusive iequalities appear B for < x < 0 ad 0< x <,
4755 Mark Scheme Jue 008 9(i) 9(ii) + j ad j B [] mark for each B [] mark for each correct pair 9(iii) ( x j)( x + j)( x+ + j)( x+ j) ( x 4x 8)( x x ) = + + + B A Attempt to use factor theorem Correct factors, mius each error if oly errors are sig errors Oe correct quadratic with real coefficiets (may be implied) 4 = x + x + x 4x 8x 8x+ 8x + 6x+ 6 4 = x x + x + 8x+ 6 Expadig A=, B=, C = 8, D= 6 OR A [7] Mius each error, A if oly errors are sig errors α = αβγδ = 6 * * * * * * αβ = αα + αβ + αβ + ββ + βα + β α * * * * * * αβγ = αα β + αα β + αββ + α ββ αβ =, αβγ = 8 A=, B =, C = 8, D= 6 OR A A [7] Both correct Mius each error, A if oly errors are sig errors Attempt to substitute i oe root Attempt to substitute i a secod root Equatig real ad imagiary parts to 0 Attempt to solve simultaeous equatios A=, B =, C = 8, D= 6 A A [7] Both correct Mius each error, A if oly errors are sig errors
4755 Mark Scheme Jue 008 Qu Aswer Sectio B (cotiued) 0(i) r r+ = r + r ( ) r= r= r= ( ) ( )( ) ( ) ( ) ( ) = + + + + 4 6 = + + + + ( )( 7 ) = + + + ( )( )( ) = + + + Mark A E [5] Commet Separatio of sums (may be implied) Oe mark for both parts Attempt to factorise (at least two liear algebraic factors) Correct Complete, covicig argumet 0(ii) r = ( + ) = ( + )( + )( + ) r r =, LHS = RHS = Assume true for = k k r r k k r = k k k + r = r ( + ) = ( + )( + )( + ) ( r+ ) k( k )( k )( k ) ( k ) ( k ) ( k )( k ) [ k( k ) ( k ) ] = + + + + + + = + + + + + ( k )( k )( k k ) = + + + + ( k )( k )( k )( k 4) ( k ) (( k ) ) (( k ) ) ( ( k ) ) = + + + + = + + + + + + + But this is the give result with k + replacig k. Therefore if it is true for k it is true for k +. Sice it is true for k =, it is true for k =,, ad so true for all positive itegers. E A A E E [8] must be see Assumig true for k (k + )th term Attempt to factorise Correct Complete covicig argumet Depedet o previous A ad previous E Depedet o first ad previous E Sectio B Total: 6 Total: 7 4