Limit & Derivative help

Hi there,

I'm floundering here, and could use some insight, I have read through the paper posted regarding epsilon-delta proofs, but I'm having trouble swallowing the information. Perhaps it's been too long since I took Calc courses, and maybe I should buy one of those Calc for dummies books :) I apreciate any help you can give.

** Use the formal delta-epsilon definition of
lim f(x) = L to prove that
x -> a
lim (mx+b) = mc+b
x->c


**Use the definition of the derivative to prove that
D (mx + b)=m
..x

and discuss the relationship of definite integral to the derivative

The main strategy in limit proofs is to start with and try to find a formula for in terms of . That way, we can say that



For the first problem, we want to find a for every such that



which amounts to saying



Can you think of a formula for , expressed in terms of , that would make the above statement true?