How do you find the antiderivative of e2x1+(e4x)dx?

1 Answer
Dec 12, 2016

12arctan(e2x)+C

Explanation:

e2x1+e4xdx

Let u=e2x so du=2e2xdx.

=122e2x1+(e2x)2dx

=1211+u2du

This is the arctangent integral:

=12arctan(u)+C

=12arctan(e2x)+C

Another way to show this is to use the trigonometric substitution e2x=tan(θ).