U-sub integral: Not sure where i went wrong.

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dwdoyle8854
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Homework Statement



Im not sure what i did wrong, every operation i took to evaluate the integral seems valid. I took pictures of the integral evaluated two different ways, producing two different answers. What bugs me is even if i evaluate (as i did) from say 0 to 1 the numbers are different, so they are not equivalent. I don't see any errors in the first one, but the textbook lists the latter as a correct answer.

The incorrect way:
2QfhdVs.jpg

Correct:
24E2jat.jpg

Homework Equations





The Attempt at a Solution


The incorrect way:
<a href="[PLAIN]http://imgur.com/2QfhdVs"><img src="http://i.imgur.com/2QfhdVs.jpg?1" title="Hosted by imgur.com" alt="" /></a>[/PLAIN]

Correct:
<a href="[PLAIN]http://imgur.com/24E2jat"><img src="http://i.imgur.com/24E2jat.jpg" title="Hosted by imgur.com" alt="" /></a>[/PLAIN]
 
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dwdoyle8854 said:

Homework Statement



I'm not sure what i did wrong, every operation i took to evaluate the integral seems valid. I took pictures of the integral evaluated two different ways, producing two different answers. What bugs me is even if i evaluate (as i did) from say 0 to 1 the numbers are different, so they are not equivalent. I don't see any errors in the first one, but the textbook lists the latter as a correct answer.

The incorrect way:
[ IMG]http://i.imgur.com/2QfhdVs.jpg?1[/PLAIN]
Correct:
[ IMG]http://i.imgur.com/24E2jat.jpg[/PLAIN]

Homework Equations



The Attempt at a Solution


The incorrect way:
<a href="[PLAIN]http://imgur.com/2QfhdVs"><img src="http://i.imgur.com/2QfhdVs.jpg?1" title="Hosted by imgur.com" alt="" /></a>[/PLAIN]

Correct:
<a href="[PLAIN]http://imgur.com/24E2jat"><img src="http://i.imgur.com/24E2jat.jpg" title="Hosted by imgur.com" alt="" /></a>[/PLAIN]
Your error is in doing basic algebra with a rational expression.

[itex]\displaystyle \frac{u}{u^2-2u+2}\ne\frac{u}{u^2}-\frac{u}{2u}+\frac{u}{2}[/itex]

After all, is [itex]\displaystyle \ \ \frac{1}{1+2+3}=\frac{1}{1}+\frac{1}{2}+\frac{1}{3}\ ? \ \[/itex]
 
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oh christ. I am dumb.

Apologies.