The domain of $f(x)=\sin \left(\log \left(\sqrt{\frac{4-x^2}{1-x}}\right)\right)$ is
Answer & explanation
Correct answer: option 1
Given $f(x)=\sin \left(\log \sqrt{\frac{4-x^2}{1-x}}\right)$
domain of sin x is R. But domain of log x is x > 0. Hence domain of given function is values of x such that $\sqrt{\frac{4-x^2}{1-x}}>0 \Rightarrow \frac{4-x^2}{1-x}>0$
$\Rightarrow \frac{(x-2)(x+2)}{x-1}>0$
$\Rightarrow x \in(-2,1) \cup(2, \infty)$
Hence (1) is the correct answer.