MATHEMATICS · Single correct · AP · Calculus AB · Differentiation: Definition and Fundamental Properties · Differentiation: Definition and Fundamental Properties
Problem
Let
f(x)={ax2,∣x−1∣+a,x≤1,x>1.
Which statement about the continuity and differentiability of f at x=1 is true?
(a) f is continuous for all real a but never differentiable at x=1.
(b) f is continuous and differentiable at x=1 for all real a.
(c) f is continuous for all real a and differentiable at x=1 only when a=21.
(d) f is continuous for all real a and differentiable at x=1 only when a=1.