Question

The domain of $f\left(x\right)=\frac{1}{\sqrt{(x-1)(x-2)(x-3)}}$ is

• A. $(-\infty ,1)\cup (3,\infty )$
• B. $(1,2)\cup (3,\infty )$
• C. $(-\infty ,2)$
• D. R

Answer 1

The correct option is B $(1,2)\cup (3,\infty )$

$f\left(x\right)=\frac{1}{\sqrt{(x-1)(x-2)(x-3)}}$

Thus $(x-1)(x-2)(x-3)>0$

Thus $x\in (1,2)\cup (3,\infty )$

Answer is option B