How do you integrate int xsec^2xxsec2x by integration by parts method?

1 Answer
Aug 1, 2016

xtanx + ln|cosx|+Cxtanx+ln|cosx|+C

Explanation:

int xsec^2x dxxsec2xdx

Integration by parts: int f(x)g'(x) dx = f(x)g(x) - int f'(x)g(x) dx

In this example: f(x)=x -> f'(x) = 1
and g'(x)=sec^2x -> g(x) = tanx

Therefore: int xsec^2x dx = xtanx - int(1*tanx) dx

int xsec^2x dx = xtanx - int tanx dx

= xtanx + ln|cosx|+C (Standard integral)