The so-called integration by parts formula is a direct consequence of Leibniz's formula for derivation of a product (v.s. 5):

In each example, we have to decide who is and who is .

We choose: Therefore: .

In this case it is wise to choose , so the logarithm will ``disappear'':

Therefore:

Thew following example uses the same technique, and its result should be remembered.

Noah Dana-Picard 2007-12-28