Let be a twice–differentiable function whose first derivative is

MATHEMATICS · Single correct · A Level · Mathematics · Differentiation · Differentiation

Problem

Let

f

be a twice–differentiable function whose first derivative is

f'(x)=x^{3}-6x

. At which

x

–value(s) does the graph of

f

have a point of inflection? (a)

x=\pm 2

(b)

x=\pm\sqrt{2}

(c)

x=0

only (d)

x=0,\,\pm\sqrt{6}