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Examine the following function for continuity: f(x)1x-5,x≠5 - Mathematics

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Question

Examine the following function for continuity:

`f (x)1/(x - 5), x != 5`

Sum

Solution

Let a be a real number, then,

`lim_(x->a^+)f(x) = lim_(h->0) 1/(a + h - 5) = 1/(a - 5)`

`lim_(x->a^-) f(x) = lim_(h->0) 1/(a - h - 5) = 1/(a-5)`

`f (a) = 1/(a-5)`

`∵ lim_(x->a^+) f(x) = lim_(x->a^-) f(x) = f(a)`

Hence, the given function `f (x) = 1/(x - 5)` is continuous at all points except at x = 5.

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Chapter 5: Continuity and Differentiability - Exercise 5.1 [Page 159]

APPEARS IN

NCERT Mathematics [English] Class 12
Chapter 5 Continuity and Differentiability
Exercise 5.1 | Q 3.2 | Page 159

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