Find the particular solution to y"=3sin(x) given the general solution

Question

y=-3sin(x) +Ax+B and the initial conditions y (π/2)=π and y'(π/2)=2

Answer 1

same old same old ...
y" = 3sinx
y' = -3cosx+A
since y'(π/2) = 2,
y' = -3cosx+2
y = -3sinx+2x+B
since y(π/2) = π, -3+π+B = π
y = -3sinx+2x+3