齐次方程的特征方程为r^2-2r+5=0r=(2±2i)/2=1±i(i是虚单位）所以齐次通解是y=e^x(C1cosx+C2sinx)设非齐次特解为y=e^x(asin2x+bcos2x)y'=e^x(asin2x+bcos2x)+e^x(2acos2x-2bsin2x)=e^x[(a-2b)sin2x+(2a+b)cos2x]y''...