Can someone help with these two questions.

Determine the length of the given curve

from 0 to

from 1 to

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- Mar 28th 2009, 01:30 PMchengbinLength of a curve
Can someone help with these two questions.

Determine the length of the given curve

from 0 to

from 1 to - Mar 28th 2009, 02:16 PMrunning-gag
- Mar 28th 2009, 02:35 PMchengbin
Thanks, I know that, but I just can't get the answer in my solution book. So I was hoping someone will write a step by step instruction of solving it.

- Mar 28th 2009, 02:48 PMrunning-gag
If you apply the formula for the first one

which can be solved by parts - Mar 28th 2009, 03:17 PMchengbin
And I don't know how to integrate

- Mar 28th 2009, 05:52 PMDeMath
- Mar 28th 2009, 06:14 PMchengbin

??? - Mar 28th 2009, 06:32 PMDeMath

Do you understand it?? (Nod) - Mar 28th 2009, 06:38 PMchengbin
OMG, that's the dumbest mistake I've done in a long time.

Oh I found out how to integrate it using integration by parts.

I'm not sure how your way of doing it works.

Anybody help me with the other one? y=lnx - Mar 29th 2009, 09:15 AMrunning-gag
For the first one there is a more simpler way by parts

where u = 2x

- Mar 29th 2009, 09:34 AMADARSH
- Mar 29th 2009, 09:47 AMADARSH
- Mar 29th 2009, 02:59 PMchengbin
I got y=x^2 now. It was a pain the in butt to do it. I'll just write my steps here to ask if there is a better way.

From 0 to

Let

When x=0,

When ,

Let

This is one ugly integral. - Mar 29th 2009, 05:32 PMmr fantastic