Understanding the Step of Integrating $\int u*v'$

Thread starter N468989
Start date Oct 5, 2007
Tags

Integrating

Oct 5, 2007

N468989

Homework Statement

\int4x^-3*ln(9x)

Homework Equations

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

The Attempt at a Solution

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

but i don't understand the step \int u*v'

if any could help me...thanks

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Oct 5, 2007

mjsd

Homework Helper

what don't you understand

u means u
v' means dv

Oct 5, 2007

N468989

Solved

thks i understand now

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