Question

find the difference quotient for the following:
a. f(x)=x-15
b. f(x)=x^2-x+3

Answer 1

((x+h)-15-x+15)/h = (x+h-15-x+15)/h = 1

Answer 2

do you see what I did?

((x+h)-f(x))/h

b)
(x+h)^2-(x+h)+3-(x^2-x+3))/h

(x^2+2xh+h^2-x-h+3-x^2+x-3)/h = (2xh+h^2-h)/h = 2x+h-1

then run the limit (not sure if you are asking for this part)


2x-1

Answer 3

no limit thats all

Answer 4

do you see what I am doing to solve these, the biggest problem that students do is forget to distribute the negative through on the - f(x) part.