Let for . Which of the following sets describes all real numbers where…

MATHEMATICS · Single correct · CBSE · Mathematics · Continuity and Differentiability · Continuity and Differentiability

Problem

Let

f(x)=\dfrac{\sin x}{x}

for

x\neq0

. Which of the following sets describes all real numbers where

f'(x)

exists? (a)

\mathbb R\setminus\{\tfrac{\pi}{2}+k\pi\mid k\in\mathbb Z\}

(b)

\mathbb R\setminus\{0\}

(c)

\mathbb R\setminus\{k\pi\mid k\in\mathbb Z\}

(d)

\mathbb R