A function is said
to be differentiable in an interval [a, b] if it is differentiable at every point of [a, b] As
in case of continuity, at the end points a and b, we take the right hand limit and left hand
limit, which are nothing but left hand derivative and right hand derivative of the function
at a and b respectively Similarly, a function is said to be differentiable in an interval
(a, b) if it is differentiable at every point of (a, b) Rationalised 2023-24
 MATHEMATICS
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Theorem 3 If a function f is differentiable at a point c, then it is also continuous at that
point