Question

Let $f(x) = |sinx|$. Then

• A. $f$ is everywhere differentiable
• B. $f$ is everywhere continuous but not differentiable at $x = n\pi$, $n\in Z$
• C. $f$ is everywhere continuous but not differentiable at $x=\left(2n+1\right) \frac{\pi}{2}$, $n \in Z$
• D. None of these

Answer 1

Answer: (B)

From the graph of $f(x) = |sinx|$, it is clear that $f(x)$ is continuous everywhere but not differentiable at $x = n\pi$, $n \in Z$.