Questions on Algebra: Functions, Domain, NOT graphing answered by real tutors!

Algebra ->  Algebra -> Questions on Algebra: Functions, Domain, NOT graphing answered by real tutors!     (Log On)
Ad: Algebra Solved!™: algebra software that solves YOUR algebra homework problems with step-by-step help!


Question 151795: f(x)=3x^2-2x+4 ; find f(x+h)-f(x): f(x)=3x^2-2x+4 ; find f(x+h)-f(x)
Answer by orca(336) About Me  (Show Source):
You can put this solution on YOUR website!
If f(x)=3x^2-2x+4, then
f(x + h)
= 3(x + h)^2 -2(x + h) + 4
=3(x^2 + 2hx + h^2) - 2(x + h) +4
= 3x^2 + 6hx + 3h^2 - 2x -2h + 4
So
f(x+h)-f(x)
= 3x^2 + 6hx + 3h^2 - 2x -2h + 4 - (3x^2 - 2x + 4)
= 3x^2 + 6hx + 3h^2 - 2x -2h + 4 - 3x^2 + 2x - 4
= 6hx + 3h^2 - 2h