Hello, brd_7!

I don't know what "C" you're referring to . . .

Find the solution of: .

The characteristic equation is: .

. . which has roots: .

The homogeneous solution is: .

Then the particular solution is of the form: .

. . and (by your favorite method) we find that: .

Therefore, the solution is: .

Without further information, we cannotevaluate the C's.