Limit describes that a function approaches as the input approaches to some value. Limits are used to define derivatives, integrals and continuity.
One sided limits are also used here. A variable approaches a fixed point either from above or below.
Example: x → 3+ or x → 3 -
Limit of a function can be found by comparison with two other functions. This is the squeeze theorem.
(a) 0 (b) 1 (c) Not defined (d) 1/2
(a) 1 (b) 0 (c) Not defined (d) -2