$\int \frac{2}{x^4-1} d x=$
Answer & explanation
Correct answer: option 3
$\int(\frac{1}{x^2-1}-\frac{1}{x^2+1})dx$
So, $\frac{1}{2}log|\frac{x-1}{x+1}|-tan^{-1}x+C$
So, option 3 is correct.
$\int \frac{2}{x^4-1} d x=$
Correct answer: option 3
$\int(\frac{1}{x^2-1}-\frac{1}{x^2+1})dx$
So, $\frac{1}{2}log|\frac{x-1}{x+1}|-tan^{-1}x+C$
So, option 3 is correct.