# Integral of (lnx)^2

1. Dec 4, 2004

### timon00

can anyone help me ?? i cant seem to do it i dont know what to do i tried by parts and substitution

2. Dec 4, 2004

### Tide

HINT:

$$\int (\ln x)^2 dx = \int \frac {dx}{dx} (\ln x)^2 dx$$

3. Dec 4, 2004

### timon00

sorry to say but i dont get that hint , can u exlain more plz

thanks

4. Dec 4, 2004

### shmoe

When you tried integration by parts, how did you break it up? Do you know how to find the simpler integral $\int\ln(x)dx$ by parts?

5. Dec 4, 2004

### Tide

It's just integration by parts:

$$\int (\ln x)^2 dx = \int \frac {dx}{dx} (\ln x)^2 dx = x (\ln x)^2 - \int x \frac {d (\ln x)^2}{dx} dx$$

You should be able to handle the rest.