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

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Question

Examine the following function for continuity:

f(x) = `1/(x - 5)`, x ≠ 5

Sum
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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]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 5 Continuity and Differentiability
Exercise 5.1 | Q 3.2 | Page 159

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