Question

Find the domain of definition of the following function:
$y=\frac{\log x}{\sqrt{x^2-2x-63}}.$

Answer 1

For

$\log xx>0$

and

$x^2-2x-63>0(x-9)(x+7)>0x\in (-\infty ,-7)\cup (9,\infty )$

Taking intersection, we get

$x\in (9,\infty )$