Originally Posted by

**reina** Hello, I've managed to solve (at least I think) the following problem:

Find the average rate of change of f(x) = 2x^{2} -x + 1 on the interval [3, 3+h].

Though I solved it in 2 different ways and ended up with 2 different answers. My answers were -7 or -11 + 2h. I'm not sure which is the right answer or if neither is right. I'm positive I managed to set up the formula correctly, which I showed below:

F(x) = (2(3+h)^{2} - (3+h) + 1 - 16)/3+h-3

Any help is appreciated, and if you provide an explanation I would be even more thankful.