Find $f'(x)$ .

On the grid below, sketch the graph of $y = f'(x)$ .

evidence of choosing the product rule     (M1)

e.g. $x \times ( - \sin x) + 1 \times \cos x$

$f'(x) = \cos x - x\sin x$     A1A1     N3

[3 marks]

     A1A1A1A1     N4

Note: Award A1 for correct domain, $0 \le x \le 6$ with endpoints in circles, A1 for approximately correct shape, A1 for local minimum in circle, A1 for local maximum in circle.

[4 marks]

This problem was well done by most candidates. There were some candidates that struggled to apply the product rule in part (a) and often wrote nonsense like $- x\sin x = - \sin {x^2}$ .

In part (b), few candidates were able to sketch the function within the required domain and a large number of candidates did not have their calculator in the correct mode.