Solution
= Solution
\b[No.] Take $f(x)=x^2$, $a=0$, and $g(y)=|y|$. The <function> $g$ is not <differentiable> at $f(0)=0$, but $g(f(x))=x^2$ is <differentiable>. Neither <function> is constant on an interval.
= Solution
\b[No.] Take $f(x)=x^2$, $a=0$, and $g(y)=|y|$. The <function> $g$ is not <differentiable> at $f(0)=0$, but $g(f(x))=x^2$ is <differentiable>. Neither <function> is constant on an interval.