FOR EDEXCEL GCE Examinations Advanced Subsidiary Core Mathematics C1 Paper L 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 L – Marking Guide 1. 2. 3. = 49 + ( 3 8 )2 = 7 + 22 = 11 5 +1 3 B1 M1 A1 (a) u4 = (b) 5= M1 A1 14 A1 =2 B1 u2 + 1 , u2 = 14 3 u +1 = 1 , u1 = 41 3 (a) b2 − 4ac = 122 − (4 × 4 × 9) = 0 ∴ 1 real root (b) 4x2 + 12x + 9 = 8 4x2 + 12x + 1 = 0 M1 8 = −12 ± 8 2 M1 = − 32 ± A2 8 2 (a) 5x > 15 x>3 (b) (x + 2)(x − 8) < 0 (c) 3<x<8 (a) (2 − −2 M1 M1 A1 8 B1 (b) = (2 − (c) = = 6. (a) (b) (6) x )2 = 0 x =2 x=4 ∫ ∫ (6) M1 A1 −2 < x < 8 5. (4) M1 A1 x = −12 ± 144 − 16 4. (3) M1 A1 3 )2 = 4 − 4 3 + 3 = 7 − 4 3 M1 A1 x )2 dx (2 − (4 − 4 x + x) dx 3 2 = 4x − 8 3 grad = −4 − 6 1 − (−3) x + 1 2 B1 x2 + c M1 A2 = − 52 M1 A1 ∴ y − 6 = − 52 (x + 3) M1 2y − 12 = −5x − 15 5x + 2y + 3 = 0 A1 2 k m: y = − x − 7 k ∴ grad = − l and m perp. ∴ − 52 × − 2 k 2 k M1 A1 = −1 M1 k = −5 C1L MARKS page 2 (8) A1 (8) Solomon Press © Science Exam Papers 7. (a) (b) 8. (a) f(x) = ∫ (5 + 4 x2 ) dx f(x) = 5x − 4x−1 + c M1 A2 f(1) = 5 − 4 + c = 1 + c f(2) = 10 − 2 + c = 8 + c f(2) = 2f(1) ∴ 8 + c = 2(1 + c) c=6 f(x) = 5x − 4x−1 + 6 f(4) = 20 − 1 + 6 = 25 M1 M1 A1 LHS = (x + 1)(x2 − 7x + 12) = x3 − 7x2 + 12x + x2 − 7x + 12 = x3 − 6x2 + 5x + 12 = RHS M1 M1 A1 (b) M1 A1 (8) y (0, 12) B3 (−1, 0) O (c) (3, 0) (i) (4, 0) x y (ii) y (0, 12) B2 B2 O (0, 0) (1, 0) (−4, 0) x (−4, 0) (−3, 0) (1, 0) O x (10) 9. 10. = (t 2 − 5) − (t − 1) = t 2 − t − 4 = (t 2 − 5) + (t 2 − t − 4) = 2t 2 − t − 9 (a) (i) (ii) (b) 2t 2 − t − 9 = 19 2t 2 − t − 28 = 0 (2t + 7)(t − 4) = 0 t>0 ∴t=4 M1 A1 (c) a = 4 − 1 = 3, d = 16 − 4 − 4 = 8 u10 = 3 + (9 × 8) = 3 + 72 = 75 B1 M1 A1 (d) = (a) A (0, 2) B1 dy = 3 − 2x dx M1 A1 grad = 3 ∴ y = 3x + 2 M1 A1 (b) 40 2 M1 A1 M1 A1 [6 + (39 × 8)] = 20 × 318 = 6360 M1 A1 (11) grad of m = 3 grad of curve at B = −1 3 = − 13 M1 A1 at B: 3 − 2x = − 13 x= 5 3 M1 A1 5 2 y = 2 + 3( 53 ) − ( 3 ) = 4 29 ∴ B ( 1 23 , 4 29 ) Solomon Press M1 A1 (11) Total (75) C1L MARKS page 3 © Science Exam Papers Performance Record – C1 Paper L Question no. 1 2 3 4 5 6 7 8 9 10 Topic(s) indices recur. relation quad. formula inequals surds, integr. straight lines integr. curve sketch, transform. AP diff., tangent Marks 3 4 6 6 8 8 8 10 11 11 Total Student C1L MARKS page 4 Solomon Press © Science Exam Papers 75