Im not quite sure what trial particular integral to use for this equation $\displaystyle \frac{d^2y}{dx^2}-3\frac{dy}{dx}+2y=2e^x-5e^(2x)$ I get the complementary function to be $\displaystyle Ae^x+Be^(2x)$ Do i needto include a minus in my trial particular integral,,or an x^2? I wouldnt have thought i need a x^2 any ideas??