# Thread: Particular solution of 2nd order ODE

1. ## Particular solution of 2nd order ODE

I was doing this question y''+3y'=cos(x)+1 and when finding the particular solution wasnt sure if I could use y=Acos(x)+Bsin(x) becuase of the +1.

Is this the right method for this question?

2. Yes, you do for the $\cos x$ but you'll also need $y_p = Ax$ for the 1 term.

3. So I am finding two particular solutions?

4. Yes - one for each of the nonhomogeneous terms (the two different types of terms).