Question:
Mark (√) against the correct answer in the following:
Let $f(x)=\frac{x}{\left(x^{2}-1\right)} \cdot$ Then, dom $(f)=?$
A. R
B. $R-\{1\}$
C. $R-\{-1\}$
D. $R-\{-1,1\}$
Solution:
$f(x)=\frac{x}{x^{2}-1}$
$x^{2}-1 \neq 0$
$x \neq(1,-1)$
$\therefore \operatorname{Dom}(f)=\mathrm{R}-\{-1,1\}$