Lane, I divided 3x^2+6x by two and got y'=3/2x^2+3x.
By power of x, I take it you mean power of 2? I neglected to put that in here, but it is on my scratch paper, I appologize.
I don't see where the arithmetic is flawed? I certainly believe that that is likely not the equation/form that I need, but I believe I worked what I figured to be correct out correctly. Can you be more specific?