# Calculus

posted by
**Amber**
.

Instructions were evaluate the integral.

(x/1-x^4) dx

I know that this form is the tanh inverse 1/1-x^2 but not sure how to substitute and start this problem. Please Help.

posted by
**Amber**
.

Instructions were evaluate the integral.

(x/1-x^4) dx

I know that this form is the tanh inverse 1/1-x^2 but not sure how to substitute and start this problem. Please Help.