Mathematics

Problem

Which of the following best defines a critical point of a function

f

? a) A number

c

for which

f'(c)\neq 0

but

f''(c)=0

b) A number

c

in the interior of the domain of

f

at which

f'(c)=0

f'(c)

does not exist c) A number

c

where

f(c)=0

d) An endpoint

c

of the interval on which

f

is defined for which

f'(c)=0