Hey guys, I was looking at an exam I did last year and tried to solve a question, which at the time I couldn't do. Unfortunately I'm running into the same problem I had during the exam, so hear me out on this one Question: The graph below has equation y =ax(x-b)(x+c)^d. Write down the values for a, b, c and d. Okay, so there's an intercept at x=-1, so b=-1. There's another intercept at x=3, so c = -3 So, y = ax(x+1)(x-3)^d Now here's the problem, the answers simply say "d = 3", and then sub in the point (1,-16) and solve for a, But at x=3 (where it's a point on inflexion), can't the degree (d) be ANY odd number? ie. 3,5,7,9,11,...,999999? Because that's how I learnt polynomials, a point on inflexion at a root means the degree of the root is odd. And so that's where I messed up, becausing I couldn't figure what value of 'd' I should use. I must obviously be missing some sort of concept, so can someone please help me out?