(adsbygoogle = window.adsbygoogle || []).push({}); 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.

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# Homework Help: Diff. Eq.'s with right sides

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