1. The problem statement, all variables and given/known data y''-5y'+4y = f(x) where I need to find a -general solution if f(x) = 0 -particular solution if f(x) = 8(x^2) - 25 -particular solution if f(x) = 9e^(x) -general solution if f(x) = (3e^x) - (8x^2) + 25 2. Relevant equations I just completed a few second order differential equations, using the method of variation of parameters to find general solutions, but this sort of question puzzles me. The other questions I have done provided one general solution and I worked with that. 3. The attempt at a solution I presume the method of variation is used for this but I have some problems on how to exactly apply it. For f(x)=0 can I use y=0 as a solution to the differential equation and how do the other f(x) alter my approach? Any help or advice would be great. Thanks in advance.