At a stationary point of a twice–differentiable function

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

Problem

At a stationary point

x=c

of a twice–differentiable function

f

, which one of the following conditions guarantees that

f

attains a local maximum at

c

? (a)

f''(c)>0

(b)

f''(c)<0

(c)

f''(c)=0

(d)

f''(c)\ge 0