#need help in another integral
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$\int_{1}^{\infty}\frac{\ln(x)}{x\sqrt{x^2-1}}dx$
myswordslaysfrrrr
Are these competitive integrals?
Anyways, trig-sub, and then queen's rule meaning let u=pi/2 - x.
Can’t you use Feynman’s technique then integrate ?
Like if you let I(t)= ∫ln(xt)/(xsqrt(t^2-1)) dx
You can evaluate I’(t) by using the substitution x=cosh(u)
I’m not sure if it works but you could try
But idk
@vast knot
$\int^{\infty}_{1}\frac{\ln{(x)}}{x\sqrt{x^2-1}}dx$
$\int^{\infty}_{0}\frac{1}{\sqrt{e^{2u}-1}}du$
$\int^{\infty}_{0}\frac{1}{2(v+1)\sqrt{v}}dv$
idk...
No Lifer (no lifer)
myswordslaysfrrrr
AoPS
Gotcha