# How do you find the Integral #(ln(3x))^2dx#?

##### 2 Answers

Try Substitution and Integration by Parts to get:

We try

Substitution doesn't seem to be working, so try the next less simple method Integration by Parts.

Try something, judge whether we seem to be making progress.

(Yes, really. There's no cookbook to solve every problem.)

Well, we can't integrate, so let's differentiate.

Let

With these choices, we get

Applying Integration by Parts gives us

(By parts, to get

With

Note: you can learn a lot, by checking the answer by differentiating.