MATHEMATICS · Single correct · A Level · Mathematics · Differentiation · Differentiation
Problem
For the function f(x)=∣x∣, which of the following statements about x=0 is correct?
(a) It is a critical point but not an extremum.
(b) It is both a critical point and a point of local minimum.
(c) It is not a critical point because f′ exists at x=0.
(d) It is a point of local minimum but not a critical point.