about quartic function... asap!!! hey everyone, I'm stuck with a proof of quartic function. For math, I was given a w shape quartic function. I was asked to find the coordinates of the points of inflection Q and R. Then to determine the points P and S, where the line QR intersects the quartic function again, and calculate the ratio PQ:QR:RS. The ratio was, after all, 1:1.618...:1. Then my teacher said to prove that every w shape quartic function gives the same ratio, but I don't know how to start. He said not to deal with massive amount of calculation, so I think I should use f"(x)=(x-a)(x-b) or something. Can anyone help me????