Hello Azmat
Suppose function is
f(x) = { x, x >= 0,
-x, x < 0
For x = 1,
Left side of 1, f(x) = x
Right side of 1, f(x) = x
Since function is same on left and right side. Then we do not need Left hand limit and right hand limit.
If for x = 0,
Left side of 0, f(x) = -x
Right side of 0, f(x) = x
Since function is different on left side and right side. We need to find Left hand limit and right hand limit and check continuity