If for every ε > 0, there exists a δ > 0 such that if 0 < | x-a | < δ , then |f(x) - L| < ε
Steps on proving limits
First find the delta value, then do the proof of the limit
lim as x approaches a f(x) = L
f(x) is defined on an open interval that contains "a" except possibly the value of "a" itself.
In your proofs, make sure to add
Choose E > 0, Let D= the delta that you solved for, Assume | x -a | < Delta
Continuity
A function is continuous if it isn't broken up
To be continuous at a point x=g
lim of f(x) as x approaches g- = L and lim of f(x) as x approaches g+= M are equal to each other & f(g)= L, which has to equal the same number/has to exist
Removable Discontinuity
There is a "hole" in the graph
Jump Discontinuity
There is a "jump" in the graph
Intermediate Value Theorem
If f if continuous on [a,b] and k is a number between f(a) and f(b), then there exists at least one number c such that f(c) = k
Includes the point (point is filled in)
Backets [ ]
Does not include the point (point if not filled in)
Parenthesis()
Delta is the distance from a number *remember to subtract!