Introduction
Limit and Derivative of Class 11
Definition (Limits)
Let f(x) be a function of x. If for every positive number ∈ there exists a positive number δ, such that 0 < |x-a| < δ we have.
|f(x) – l| < ∈ then we say
f(x) tend to limit l as x tend to a and we write f (x) = l.
Right Hand And Left Hand Limits
In the definition of the limit we say that l is the limit of f(x) if f(x) → l when x → a.
If we modify the definition a little further that is when x → a from the values of x > a then the corresponding limit is called the RHL (Right Hand Limit) of f(x) and is written as
Or in short f(a+0) =
Like wise f(a-) = is said to be the Left Hand Limit LHL).
If both the limits exist i.e. finite and are equal to each other than the function is said to have a definite limit.