Now set in (1) instead of ...
Does the addition of 1 change this?
Which is where you got. Let us look at the integral then.
Of course this this the same as
We then get
Edit- LOL at how many people jumped on answering this guy's question. I should quit here there's too many of us!
... is integration by parts, where
... is the product rule.
Straight continuous lines differentiate downwards (integrate up) with respect to x. Choosing legs crossed or un-crossed does for assigning u du and v dv.
Hope it helps, or amuses - but use whatever works for you.
Don't integrate - balloontegrate!
Balloon Calculus; standard integrals, derivatives and methods
Balloon Calculus Drawing with LaTeX and Asymptote!