solving constants for differential equation
If y=a+bx+cx^2 is a solution of d²y/dx² +2(dy/dx)+4y=4x², I have tried to find the values of a,b and c by taking the derivative and second derivative of the function the subbing these into the differential equation however I can't seem to cancel out much to get to a single constant to use to sub into the equation to solve the other two constants, can anyone suggest what I can do after subbing in values the derivatives of y into the DE to solve for the constants a,b and c? Is this the right approach to finding the values of a,b and c?