Question

The domain of $f\left(x\right)=\frac{1}{\sqrt{|x|-x}}$ is

• A. $(-\infty ,0)$
• B. $(0,\infty )$
• C. $(1,\infty )$
• D. $(-\infty ,\infty )$

Answer 1

Answer: (A)

$(-\infty ,0)$

$|x|-x>0$
$\Rightarrow |x|>x$
For all $x$ $+$ve $|x|=x$
For $x$ $-$ve $|x|>x$
$\Rightarrow x\in (-\infty ,0)$