A more difficult integral, general power formula

Question: Integrate 28-1-16

(int) 0.8((3 + 2 ln(u))^3) du/u

My attempt:

u = (3 + 2 ln u)

du = 2(1/u) = 2/u

My guess at this is to divide the whole integral by 2 now since it has been multiplied by 2 in the derivative.

resulting in this:

0.4[3 + 2 ln u]/4

I used a Ti-89 and got a very weird answer. Any clues as to what went wrong? thanks.

Re: A more difficult integral, general power formula

Hello, togo!

You are using for two different quantities.

We have: .

Let

Substitute: .

Back-substitute: .

Re: A more difficult integral, general power formula