Question 580658
6. The rate of change of a quadratic function *[tex \LARGE f(x) = ax^2 + bx + c] is


*[tex \LARGE \lim_{\Delta x \to 0} \frac{f(x+\Delta x) - f(x)}{\Delta x}]


You can evaluate it yourself, but if you know the chain rule you can conclude that it is equal to


*[tex \LARGE f'(x) = 2ax + b]


7. Easy, a is the coefficient of x^2, b is the coefficient of x, and c is the constant term. For example,


h(x) = x^2 - 3x


has leading coefficient 1, x coefficient -3, and 0 as the constant term. Hence


a = 1
b = -3
c = 0


Try the others the same way.