Let us definite the limit of a function. Let f(x) be a function of x, and let a be a real number. We say limx→a f(x) = L if both the left hand and the right hand limit of f(x) exist and equal. That is,
limx→a- f(x) = limx→a+ f(x) = L.
For example, limx→1 x2 = 12 = 1.
Solved Problems on Limits