Inhomogeneous equations: Variation of Parameters

[peace-Econ]

Homework Statement

Find a particular solution for these second order differential equations.

Homework Equations

1) y''+9y=tan3t

2) y''+y=tan^2t

The Attempt at a Solution

I want to find a fundamental solutions y1 and y2 because I want to find a particular solution like this y=v1*y1+v2*y2, but i don't know how to get them.

 

[hunt_mat]

Have you tried googling the method at all?

http://www.google.co.uk/search?hl=e...s:+Variation+of+Parameters&btnG=Google+Search