Integrating Expressions Involving Fractions of Trigonometric Functions Using the substitution t=tan(1/2)theta
To be able to use this method we have to expressand
in terms of
(1)
(2)
(3)
(4)
To evaluate any integral such asor
we make the substitution
and use (1), (2), (3) and (4) above to express everything in terms of t then integrate.
Example: Find
Sub (1) and (4)