Someone pls help asap! will give brainlist

Let f(x) = 3 − x . find the average rate of change of f(x) from x = a to x = a + h and simplify your answer so that no single factor of h is left in the denominator.

Find the roots of the polynomial function f(x) = x^3 + 2x^2 + x

What is the result of the following division?