# Help calculus

1. Oct 5, 2007

### N468989

1. The problem statement, all variables and given/known data

$$\int4x^-3*ln(9x)$$

2. Relevant equations

$$\int u'*v = u*v - \int u*v'$$

3. The attempt at a solution

i know the answer is $$\frac{-2ln(9x)-1}{x^2}$$

but i dont understand the step $$\int u*v'$$

if any could help me....thanks

2. Oct 5, 2007

### mjsd

what don't you understand

u means u
$$v'$$ means $$dv$$

3. Oct 5, 2007

### N468989

Solved

thks i understand now