### Arc Length Problem

Posted:

**Fri Apr 09, 2010 6:20 am**How to evaluate the length of arc of y=x^4/4 from on [0,a]? thanks.

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Posted: **Fri Apr 09, 2010 6:20 am**

How to evaluate the length of arc of y=x^4/4 from on [0,a]? thanks.

Posted: **Fri Apr 09, 2010 8:17 am**

The formula for arc length is

Sorry I edited it to simplify as you were posting!

Sorry I edited it to simplify as you were posting!

Posted: **Fri Apr 09, 2010 8:19 am**

origin415 wrote:First you want to parametrize x and y, so

x(t) = t

y(t) = t^4/4

then the formula for arc length is

I'm ok with this formula...but I'm stuck with the integral...so i want to ask for help, thanks.

Posted: **Fri Apr 09, 2010 8:30 am**

Well you can't actually do that integral, so don't try it (http://www.wolframalpha.com/input/?i=In ... %29%2Cx%29). What are the multiple choice answers? Maybe you can estimate the answer if the answers are not too close to one another.

If a is small, than is close to 1, if a is large, its close to .

If a is small, than is close to 1, if a is large, its close to .