How Do You Integrate (sec x)^4?

Thread starter teng125
Start date Jan 2, 2006
Tags

Integrate

Jan 2, 2006

teng125

May i know how to integrate (sec x)^4 ??

the answer is tan x + 1/3 (tan x)^3

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Jan 2, 2006

Pyrrhus

Homework Helper

Try writing your integral as
\int (\tan^{2} x + 1) \sec^{2} x dx

Jan 2, 2006

teng125

okok...thanx

Jan 2, 2006

fargoth

try using u=tg(x)
du=\frac{dx}{cos^2(x)}
and \frac{1}{cos^2(x)}=1+tg^2(x)=1+u^2

Last edited: Jan 2, 2006

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