Question

$\frac{1}{x+1}-\frac{1}{x-1}-\frac{x^2}{x+1}+\frac{x^2}{x-1}$, when simplified is equal to

• A. 0
• B. 1
• C. 2
• D. -2

Answer 1

The correct option is C 2

$\frac{1}{x+1}-\frac{1}{x-1}-\frac{x^2}{x+1}+\frac{x^2}{x-1}$
= $\frac{(x-1)-(x+1)-x^2(x-1)+x^2(x+1)}{(x-1)(x+1)}$
= $\frac{x-1-x-1-x^3+x^2+x^3+x^2}{x^2-1}$
= $\frac{2x^2-2}{x^2-1}=\frac{2(x^2-1)}{(x^2-1)}=2$