PhysicsAndMathsTutor.com Version 1.0: 0106 abc General Certificate of Education Mathematics 6360 MFP2 Further Pure 2 Mark Scheme 2006 examination - January series Mark schemes are prepared by the Principal Examiner and considered, together with the relevant questions, by a panel of subject teachers. This mark scheme includes any amendments made at the standardisation meeting attended by all examiners and is the scheme which was used by them in this examination. The standardisation meeting ensures that the mark scheme covers the candidates’ responses to questions and that every examiner understands and applies it in the same correct way. As preparation for the standardisation meeting each examiner analyses a number of candidates’ scripts: alternative answers not already covered by the mark scheme are discussed at the meeting and legislated for. If, after this meeting, examiners encounter unusual answers which have not been discussed at the meeting they are required to refer these to the Principal Examiner. It must be stressed that a mark scheme is a working document, in many cases further developed and expanded on the basis of candidates’ reactions to a particular paper. Assumptions about future mark schemes on the basis of one year’s document should be avoided; whilst the guiding principles of assessment remain constant, details will change, depending on the content of a particular examination paper. Copyright © 2006 AQA and its licensors. All rights reserved. PhysicsAndMathsTutor.com MFP2 – AQA GCE Mark Scheme, 2006 January series Key To Mark Scheme And Abbreviations Used In Marking M mark is for method m or dM A B E mark is dependent on one or more M marks and is for method mark is dependent on M or m marks and is for accuracy mark is independent of M or m marks and is for method and accuracy mark is for explanation or ft or F CAO CSO AWFW AWRT ACF AG SC OE A2,1 –x EE NMS PI SCA follow through from previous incorrect result correct answer only correct solution only anything which falls within anything which rounds to any correct form answer given special case or equivalent 2 or 1 (or 0) accuracy marks deduct x marks for each error no method shown possibly implied substantially correct approach MC MR RA FW ISW FIW BOD WR FB NOS G c sf dp mis-copy mis-read required accuracy further work ignore subsequent work from incorrect work given benefit of doubt work replaced by candidate formulae book not on scheme graph candidate significant figure(s) decimal place(s) No Method Shown Where the question specifically requires a particular method to be used, we must usually see evidence of use of this method for any marks to be awarded. However, there are situations in some units where part marks would be appropriate, particularly when similar techniques are involved. Your Principal Examiner will alert you to these and details will be provided on the mark scheme. Where the answer can be reasonably obtained without showing working and it is very unlikely that the correct answer can be obtained by using an incorrect method, we must award full marks. However, the obvious penalty to candidates showing no working is that incorrect answers, however close, earn no marks. Where a question asks the candidate to state or write down a result, no method need be shown for full marks. Where the permitted calculator has functions which reasonably allow the solution of the question directly, the correct answer without working earns full marks, unless it is given to less than the degree of accuracy accepted in the mark scheme, when it gains no marks. Otherwise we require evidence of a correct method for any marks to be awarded. 2 PhysicsAndMathsTutor.com AQA GCE Mark Scheme, 2006 January series – MFP2 MFP2 Q Solution 1(a) 1 r = (b) − 2 2 1 ( r + 1) ( r + 1) − r 2 r 2 ( r + 1) = 2 Marks r A1 ( r + 1)2 3 2 1 ×2 2 5 22 × 32 7 2 3 ×4 2 1 = 2 1 = 22 1 3 2n + 1 n 2 ( n + 1) 2 2 = − 1 32 1 M1A1 42 1 2 − ( n + 1)2 M1 1 A1F ( n + 1)2 Total 2(a) p = −4 (α + β + γ ) 4 6 B1 2 = ∑ α 2 + 2 ∑ αβ M1 16 = 20 + 2 ∑ αβ ∑ αβ = −2 q = −2 (b) A1 for at least 3 lines 1 Clear cancellation 1− AG 22 − n 2 1 − 1 = Comments M1 2r + 1 2 Total 2 A1 A1F A1F 3 − i is a root B1 Third root is −2 B1F αβγ = ( 3 + i )( 3 − i )( −2 ) M1 = −20 r = +20 A1F A1F Alternative to (b) Substitute 3 + i into equation 5 Real αβγ 5 Real r M1 B1 2 ( 3 + i ) = 8 + 6i 3 ( 3 + i ) = 18 + 26i B1 r = 20 A2,1,0 Total Provided r is real 10 3 PhysicsAndMathsTutor.com MFP2 – AQA GCE Mark Scheme, 2006 January series MFP2 (cont) Q Solution Marks Total M1A1 2 M1A1 2 Comments 2 3(a) (b) (c) 1 + i (1 + i ) = =i 1 − i 1 − i2 z2 = 1 3 + = 1 = z1 4 4 r =1 1 1 θ = π, π 2 3 B1 AG PI B1B1 3 Deduct 1 mark if extra solutions B2,1F 2 Positions of the 3 points relative to each other, must be approximately correct (d) (e) Arg ( z1 + z2 ) = 5 tan π = 12 1+ 5 π 12 1 3 2 1 2 =2+ 3 B1 Clearly shown M1 Allow if BO earned A1 Total 4 3 12 AG must earn BO for this PhysicsAndMathsTutor.com AQA GCE Mark Scheme, 2006 January series – MFP2 MFP2 (cont) Q Solution 4(a) Assume result true for n = k Marks Total Comments k ∑ ( r + 1)2r −1 = k 2k r =1 k +1 ∑ ( r + 1) 2r −1 = k 2k + ( k + 2 ) 2k M1A1 r =1 = 2k ( k + k + 2 ) m1 = 2k ( 2k + 2 ) = 2k +1 ( k + 1) 2 × 20 = 2 = 1 × 21 B1 Pk ⇒ Pk +1 and P1 is true E1 n =1 (b) A1 2n n r =1 r =1 ∑ ( r + 1)2r −1 − ∑ ( r + 1) 2r −1 M1 = 2n 22 n − n 2n A1 ( ) = n 2n+1 − 1 2n A1 Total 6 Sensible attempt at the difference between 2 series 3 9 5 Provided previous 5 marks earned AG PhysicsAndMathsTutor.com MFP2 – AQA GCE Mark Scheme, 2006 January series MFP2 (cont) Q Marks Solution Total Comments 5(a) B1 Circle B1 Correct centre B1 (b) 3 Touching both axes z max = OK M1 Accept = 42 + 42 + 4 A1F Follow through circle in incorrect position =4 ( ) 2 +1 A1F (c) Correct position of z , ie L 3 42 + 42 + 4 as a method AG M1 1 ⎞ ⎛ a = − ⎜ 4 − 4cos π ⎟ 6 ⎠ ⎝ ( =− 4−2 3 ) A1F 1 b = 4 + 4sin π = 6 6 A1F Total 6 Follow through circle in incorrect position 3 9 PhysicsAndMathsTutor.com AQA GCE Mark Scheme, 2006 January series – MFP2 MFP2 (cont) Q 6(a)(i) Solution z+ z2 + 1 z2 (b) 1 = eiθ + e –iθ z M1 A1 2 AG 2 OE 3 AG = cos 2θ + i sin 2θ z2 − z + 2 − + cos ( −2θ ) + i sin ( −2θ ) M1 A1 1 1 + z z2 = 2 cos 2θ − 2 cos θ + 2 M1 Use of cos 2θ = 2cos 2 θ − 1 m1 = 4cos 2 θ − 2cos θ A1 z+ Comments Or z + cos ( −θ ) + i sin ( −θ ) = 2cos 2θ (iii) Total 1 = cos θ + i sin θ + z = 2cos θ (ii) Marks 1 =0 z z = ±i M1A1 Alternative: 1 z + =1 z z2 − z + 1 = 0 M1A1 z = ±i 1± i 3 2 Accept solution to (b) if done otherwise A1F Alternative 1 1 If θ = + π θ = π 2 3 M1 z= 5 M1 A1 B1 Total 12 7 θ =± π M1 A1 cos θ = z=e A1 1+ 3 i 2 Or any correct z values of θ Any 2 correct answers One correct answer only z =i z= 1 2 cos θ = 0 1 2 ± 1 πi 3 1 3 M1 ) A1 A1 θ =± π = 1 1± i 3 2 ( PhysicsAndMathsTutor.com MFP2 – AQA GCE Mark Scheme, 2006 January series MFP2 (cont) Q 7(a)(i) θ ⎛e −e 2⎜ ⎜ 2 ⎝ = (ii) −θ Solution ⎞ ⎛ e + e −θ ⎞ ⎟⎟ ⎜⎜ ⎟⎟ 2 ⎠⎝ ⎠ e 2θ − e −2θ = sinh 2θ 2 ⎛ eθ − e −θ ⎜⎜ 2 ⎝ 2 ⎞ ⎛ eθ + e −θ ⎟⎟ + ⎜⎜ 2 ⎠ ⎝ ⎞ ⎟⎟ ⎠ Total Comments M1A1 2 AG 3 AG 2 M1 e 2θ − 2 + e − 2θ + e 2θ + 2 + e −2θ 4 = cosh 2θ = (b)(i) Marks θ A1 A1 x! = 3cosh 2 θ sinh θ ′′ M1A1 Allow M1 for reasonable attempt at differentiation, but M0 for putting in terms of ekθ or sinh 3 θ unless real progress made towards x! 2 + y! 2 y! = 3sinh 2 θ cosh θ A1 Allow this M1 if not squared out, must be clear sum in question is x! 2 + y! 2 x! 2 + y! 2 = 9cosh 4 θ sinh 2 θ M1 +9 sinh 4 θ cosh 2 θ 2 2 ( 2 2 = 9 sinh θ cosh θ cosh θ + sinh θ AG ) A1 Accept 1 ∫0 9 4 sinh 2 2θ cosh 2θ dθ but limits must appear somewhere 9 = sinh 2 2θ cosh 2θ 4 (ii) S= ∫ 13 0 2 A1 sinh 2θ cosh 2θ d θ 6 AG 6 AG M1 u = cosh 2θ d u = 2 sinh 2θ d θ 1 3 2 3 2 3 I= u du = × u2 4 4 3 M1A1 ∫ A1F 1 3⎫ ⎧⎪ 1 ⎪ S = ⎨ ( cosh 2θ ) 2 ⎬ 2 ⎩⎪ ⎭⎪0 A1F 3 1⎧ ⎫ ⎨( cosh 2 ) 2 − 1⎬ 2⎩ ⎭ A1 = Total TOTAL 8 17 75