How do you find the integral of csc^2x/cot^3x dx?

1 Answer
May 22, 2018

int csc^2x/cot^3x "d"x=1/2tan^2x+"c"

Explanation:

We want to find intcsc^2x/cot^3x "d"x. Note that

csc^2x/cot^3x=1/sin^2xsin^3x/cos^3x=sinx/cos^3x=sec^2xtanx

So,

intcsc^2x/cot^3x "d"x=intsec^2xtanx "d"x

We now perform the natural substitution u=tanx and "d"u=sec^2x "d"x

Hence,

intsec^2xtanx "d"x=intu "d"u=1/2u^2=1/2tan^2x+"c"