# Thread: Second order nonhomegeneous DE

1. ## Second order nonhomegeneous DE

I am trying to solve the following:

$\displaystyle y''+y'-2y=x^{3}-e^{x}$

I have been trying to use the method of undetermined coefficients but cannot find an appropriate choice for $\displaystyle y_{p}(x)$.

2. ## Re: Second order nonhomegeneous DE

To find the particular solution corresponding to -exp(x), try A*x*exp(x) and compute A;
To find the particular solution corresponding to x^3, try B*x^3 +C*x^2 +D*x+E and compute B, C, D and E.