FOR EDEXCEL GCE Examinations Advanced Subsidiary Core Mathematics C1 Paper E MARKING GUIDE This guide is intended to be as helpful as possible to teachers by providing concise solutions and indicating how marks could be awarded. There are obviously alternative methods that would also gain full marks. Method marks (M) are awarded for knowing and using a method. Accuracy marks (A) can only be awarded when a correct method has been used. (B) marks are independent of method marks. Written by Shaun Armstrong Solomon Press These sheets may be copied for use solely by the purchaser’s institute. © Science Exam Papers C1 Paper E – Marking Guide 1. 2. 3. 5. 3 3 × = (b) = 4 − 2 3 − 4 3 + 6 = 10 − 6 3 = 6 3 M1 A1 M1 A1 3x2 − 5 = 2x 3x2 − 2x − 5 = 0 (3x − 5)(x + 1) = 0 x = −1, 53 x − 5y = 7 grad m = 4. 18 3 (a) ⇒ −1 1 5 M1 M1 A2 1 5 y= x− 7 5 ∴ grad = 1 5 (4) B1 = −5 M1 A1 ∴ y − 1 = −5(x + 4) y = −5x − 19 M1 A1 (a) 1, 7, 25, 79 B2 (b) 7=a+b 25 = 7a + b subtracting, M1 A1 M1 A1 (a) (4) 6a = 18 a = 3, b = 4 (5) (6) 5 8x − x 2 = 0 3 x(8 − x 2 ) = 0 3 x = 0 (at O) or x 2 = 8 ∴ x=( 8) =4 M1 A1 dy =8− dx x2 M1 A1 grad = 8 − ( 52 × 8) = −12 M1 A1 (a) f(x) = 2[x2 − 2x] + 1 = 2[(x − 1)2 − 1] + 1 a = 2, b = −1, c = −1 = 2(x − 1)2 − 1, M1 M1 A2 (b) x=1 B1 (b) 6. (c) 7. M1 2 3 (a) 5 2 3 (7) 2 2(x − 1) − 1 = 3 (x − 1)2 = 2 x=1± 2 M1 M1 A1 2 f(x) = x − 8 x1 + 16 M1 (8) 2x 2 f(x) = (b) f ′(x) = f ′(x) = f ′(x) = C1E MARKS page 2 1 2 3 1 x 2 − 4x 2 + 8x 3 4 1 4 1 4 1 x 2 − 2x − 12 − 12 − 4x , A= 1 2 , B = −4, C = 8 − 32 x − 32 (3x2 − 8x − 16) x − 32 (3x + 4)(x − 4) = A2 M1 A2 M1 (3x + 4)( x − 4) M1 A1 3 (9) 4x 2 Solomon Press © Science Exam Papers 8. (a) translation by 1 unit in the positive x-direction (b) B2 y y=0 O x B3 (0, −1) x=1 (c) 1 x −1 =2+ 1 x x = 2x(x − 1) + (x − 1) 2x2 − 2x − 1 = 0 9. (a) M1 A1 x= 2± 4+8 4 M1 x= 2±2 3 4 M1 x= 1 2 ± 6 2 S6 = 1 2 3 A1 [3000 + (5 × −x)] = 8100 3000 − 5x = 2700, M1 A1 x = 60 M1 A1 (b) = 1500 − (7 × 60) = 1500 − 420 = £1080 (c) Sn = n 2 10. (a) (b) M1 A1 [3000 − 60(n − 1)] M1 = n[1500 − 30(n − 1)] = 30n[50 − (n − 1)] = 30n(51 − n) (d) [ k = 30 ] the value of sales in a month would become negative which is not possible y= ∫ (10) M1 A1 B1 (10) (3x2 + 4x + k) dx y = x3 + 2x2 + kx + c (0, −2) ∴ c = −2 (2, 18) ∴ 18 = 8 + 8 + 2k − 2 k=2 3 y = x + 2x2 + 2x − 2 M1 A2 B1 M1 A1 A1 x3 + 2x2 + 2x − 2 = x − 2 x3 + 2x2 + x = 0 x(x2 + 2x + 1) = 0 x(x + 1)2 = 0 repeated root ∴ tangent point of contact where x = −1 ∴ (−1, −3) M1 M1 A1 M1 A1 (12) Total (75) Solomon Press C1E MARKS page 3 © Science Exam Papers Performance Record – C1 Paper E Question no. 1 2 Topic(s) surds quad. Marks 4 4 3 4 5 straight sequence, indices, diff. lines recur. relation 5 6 7 6 7 8 9 10 compl. square diff. transform., quad. formula AP integr., rep. root 8 9 10 10 12 Total Student C1E MARKS page 4 Solomon Press © Science Exam Papers 75