1. The problem statement, all variables and given/known data y''' - y = e^x + 7 2. Relevant equations 3. The attempt at a solution I used y=Ae^x +B and then I multiplied by x^2 because y_c = c1 + c2 e^x + c3 e^(-x) the c1 and c2 e^x value repeat. Therefore I got: y= Ax^2 e^x + Bx^2 I got A = 0 and A=1 which is wrong and B=0 Any hints? do I need to add a Cx e^x and then multiply by x^2?