1. The problem statement, all variables and given/known data Find a particular solution of the given differential equation. y'' + 4y = (sin^2)(x) Answer from book: yp(x)= (1/8)(1-xsin2x) 3. The attempt at a solution y'' + 4y = 4(sinx)^2.............(1) 4(sinx)^2=2 - 2cos2x Homogeneous solution: r^2+4=0 r^2= -4 r=+-2i ==> yh=C1cos(2x)+C2sin(2x) Particular solution: yp=A+Bxcos2x+Cxsin2x yp' =Bcos2x-2Bxsin2x+Csin2x+2Cxcos2x yp" = -2Bsin2x -2Bsin2x-4Bxcos2x +2Ccos2x+2Ccos2x - 4Cxsin2x Substitute y and y" in (1) ==> 4A - 4Bsin2x+4Ccos2x=2 - 2cos2x ==> A=1/2 B=0 C= -1/2 yp=1/2 - (1/2)xsin2x This is answer is different from the book. What am I doing wrong?