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?

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- Dec 13th 2012, 08:19 PMkingsolomonsgraveevaluating 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? - Dec 13th 2012, 08:36 PMchiroRe: 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] - Dec 13th 2012, 08:48 PMMarkFLRe: evaluating a definite integral
The reason your answer is wrong is because:

$\displaystyle \frac{d}{dx}\left(e^{2x} \right)\ne e^{2x}$

but:

$\displaystyle \frac{d}{dx}\left(\frac{1}{2}e^{2x} \right)=e^{2x}$

Using the substitution suggested by**chiro**is the best way to go, IMHO. - Dec 13th 2012, 08:58 PMkingsolomonsgraveRe: evaluating a definite integral
thanks!