How to Solve Second Order Linear Differential Equations with Initial Conditions?

[INeedHelpTY]

y'' = B*sin(t) - y

y(0) = A (constant)
y'(0) = 0

need some help to start this off, thanks

 

[Coto]

If you're solving second order linear differential equations, then you will need to know this:

http://tinyurl.com/3yuhxlh

Edited: After you changed your equation.