Mathematics · May / June 2020 · Paper 41 · Question 10

15.7 or 15.65... [3]

M2 for 2 2 ( 4 – 10) + (4 – –3) oe

or M1 for (–4 –10)2 + (4 – – 3)2 oe

– 10 4 – [= –2] oe 4 – – 3 10 = –2(–3) + c Or –4 = –2(4) + c and correct completion to y = –2x + 4 [2]

M1 A1

y = 1 2 x + 11 4 oe [4]

M1 for grad = ½ soi

M1 for [midpoint =] (½, 3)

M1 for substitution of (1/2, 3) into their y = mx + c oe

1 22 − , − oe and (–5, 50) 3 27 [6]

B2 for 3x2 + 16x + 5

Or B1 for one correct

M1 for derivative = 0 or their derivative = 0

M1 for [x =] – 1 3 and [ x =] –5

B1 for – 22 27 and 50

1 22 − , − minimum 3 27 (–5, 50) maximum with correct reasons [3]

B2 for one correct with reason

or M1 for correct attempt e.g. 2nd derivatives, gradients or sketching