# Ssec^3(w)dw is very easy but you need to pay atention!

1. ### kallazans

5
Ssec^3(w)dw
it is very easy if you use integration by parts, but you need to pay atention!

how about use a partial fraction ? if you like to have a hard work!!

Someone agree with me?

2. ### HallsofIvy

41,050
Staff Emeritus
Actually, the way I would do that is to write sec3w as
1/cos3(w) and sec3(w)dw as
cos(w)dw/cos4(w)= cos dw/(1- sin2(w))2, make the substitution u= sin(w) so the integral becomes
&int; du/(1-u2)2 and THEN use partial fractions. Is that what you meant?