# evaluating a definite integral

• December 13th 2012, 08:19 PM
kingsolomonsgrave
evaluating a definite integral
if I evaluate

Attachment 26216

I get e^6 - e^2 but the answer should be (1/2)(e^6 - e^2), where does the (1/2) come from?
• December 13th 2012, 08:36 PM
chiro
Re: evaluating a definite integral
Hey kingsolomonsgrave.

Try doing a transformation u = 2x where du/dx = 2 which means you have to multiply by a 1/2 and the limits go from [1,3] to [2,6]
• December 13th 2012, 08:48 PM
MarkFL
Re: evaluating a definite integral
$\frac{d}{dx}\left(e^{2x} \right)\ne e^{2x}$
$\frac{d}{dx}\left(\frac{1}{2}e^{2x} \right)=e^{2x}$