Integrate... indefinite integral (cos(radx))/rad(x) dx

Question

jennychan12 · Answer

$$\int\limits \frac{ \cos \sqrt{x} }{ \sqrt{x} }dx$$

jennychan12 · Answer

even if i use u sub, it'd be a fraction...
$$u = \sqrt {x}$$
$$du = \frac{ 1 }{ 2 }(x)^{-\frac{ 1 }{ 2 }} dx$$
2du = dx/x^1/2

jennychan12 · Answer

$$2 \int\limits \frac{ cosu }{ u } du$$

jennychan12 · Answer

anyone??

zepdrix · Answer

I don't think this one can be solved using elementary methods. It's called the "Cosine Integral".

If you look it up on Wolfram you can get some information on it. But I don't think you can go any further with it using traditional methods. Hmm :( Is this a homework problem?

jennychan12 · Answer

yes. it's in my final review packet.

zepdrix · Answer

oh oh oh i see the problem, you made a boo boo with your u sub, one sec.

jennychan12 · Answer

haha ok lemme try again

zepdrix · Answer

ok :)

zepdrix · Answer

Oh I'm sorry I should have been a little more clear, your U-sub looks good. You just didn't plug it in correctly.

jennychan12 · Answer

$$2du = x^{-1/2} dx $$
but then i don't really know how to go from there...

zepdrix · Answer

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