What is the best approach for solving the integral of x*e^cos(x) from 0 to 6?

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Homework Statement



integral of x*e^cos(x) from 0 to 6.

Homework Equations



I tried using integration by parts twice but no luck (couldn't find the integral of e^cos(x)). I was hoping I might use De Moivre's theorem but don't think it's applicable. I thought this looked a little like a La Place Transform, but couldn't find the appropriate form. Thought about integrating over a complex region, but forgot how and don't have 20 free hours to figure it out. I almost stated reading about the LeBesgue which I never understood in the first place.

The Attempt at a Solution



I punched it into wolfram alpha with some bounds and I finally got a numeric solution. What am I not seeing here, it's driving me crazy. Am I just supposed to use a graphing utility to solve this within as many significant digits that I care to compute?
 
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It looks like your only choice is a numerical solution. I don't see any other way to do it.
 
I must agree with Dick, a numerical solution is the only option I see.

** Before you go looking at complex integration - it can't be done with it's methods.
 
Alright, I appreciate the help guys.
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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