Q37 / 90 · JEE Main 2012 (26 May Online) · Mathematics
$\lim _{x \rightarrow 0} \frac{\sin \left(\pi \cos ^2 x\right)}{x^2}$ equals
- A$-\pi$
- B1
- C$-1$
- Correct answerD$\pi$
Solution
Consider
$$
\begin{aligned}
& \lim _{x \rightarrow 0} \frac{\sin \left(\pi \cos ^2 x\right)}{x^2} \\
& =\lim _{x \rightarrow 0} \frac{\sin \left(\pi-\pi \sin ^2 x\right)}{x^2} \\
& =\lim _{x \rightarrow 0} \frac{\sin \left(\pi \sin ^2 x\right)}{\pi \sin ^2 x} \times \frac{\left(\pi \sin ^2 x\right)}{x^2}=\pi
\end{aligned}
$$
Hence, the correct answer is option: 'D'.