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Really hard integrals?

  1. Jan 1, 2016 #176
    I believe this uses multivariable calculus since I recall you must first prove the definite integral of the e^-x^2 which requires double integrals and a change of variables.
     
  2. Jan 1, 2016 #177
    I think you need multivariable to do that.
     
  3. Jan 17, 2016 #178
    Here is a hard nut to crack. Been trying to solve it for a while, can't confirm it's actually solvable.

    1/ ( x ( ln (x+1) -1 ) )
     
  4. Feb 16, 2017 #179
    x^2arctan(5x)
     
  5. Mar 9, 2017 #180

    Demystifier

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    Last edited by a moderator: May 8, 2017
  6. Mar 9, 2017 #181
    $$\int_{0}^{\pi}\frac{cos(nx)-cos(na)}{cos(x)-cos(a)} dx$$

    and

    $$\int_{0}^{\infty }\frac{x}{e^{x}-1} dx$$
     
    Last edited: Mar 9, 2017
  7. Oct 13, 2017 #182
    Try this. 1507919193165-1998323113.jpg
     
  8. Dec 26, 2017 #183
    it should come from common sense i think. seems the analytical method is gonna be just WOOW
     
  9. Dec 27, 2017 #184

    ComplexVar89

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