i'm a first year student in biology from Brussels and, as most students do, have passed a math exam today. I'm not quite sure whether my solution to one of the questions is correct. I was wondering if somebody could check/confirm my answer? thx a lot ^^
The 2nd degree linear non homogenic DE is as follows :
y'' - 2y' - 3y = e^(-x)
Using the method of variation of parameters to find the particular solution Yp I found this general solution
Y = Yc + Yp = c1 e^(3x) + c2 e^(-x) – e^(-x)* ((1 + 4x) / 16)
Is this correct? I'm also wondering if I should have used the method of undetermined coefficients instead?
What I ment is you cant take derivatives of your solution and plug them into the ode and check your solution. This is exactly like solving
and plugging into it to check your solution.
IF you look at the attached immage above this code
and it did give the correct solution.