Evaluate the integral using substitution

[Econometricia]

1. Evaluate the integral [0,ln(3)] of ff(x)=(e^2x + 1)^2 /e^x



I am having trouble locating what to substitute.

 

[Mark44]

No need for a substitution. Just expand (e^2x + 1)² and divide each term by e^x.

 

[Econometricia]

haahah. Thank you Mark.Final exam time I think I'm loosing it.
Reminded me of http://jacobyap.com/wp-content/uploads/2010/02/math06.gif