Integrating Secant Cubed Times Tangent Cubed

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integral of sec3xtan3xdx

i tried to start this by rewriting secx as 1/cosx and that got me the integral of sin2x/cos6xdx

after that i tried a regular substitution but that didnt work since it doesn't take care of the sin3x on top

kinda stuck on where to go
any help?
 
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Hint: \sin^3(x)=\sin(x)[1-\cos^2(x)] :wink:
 


I would try: sec2x(sec x)(tan2x)(tan x)
 


first guys idea worked, thanks
 


tan2x = sec2x-1
 


apiwowar said:
first guys idea worked

I know, just showing you another way of going about it, with thrill3rnit3 giving you a huge hint on how to go about it.
 
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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