Thread: integration with trig substitution

integrate:

2x^2 / x^2 + 4 dx


how do know which substitution to use here and what happens to the numerator???

Originally Posted by razorfever

integrate:

2x^2 / x^2 + 4 dx


how do know which substitution to use here and what happens to the numerator???

First do some long division to turn the integrand into

.


Then you work with the fact that .