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Examine the following function for continuity: f (x) = x – 5 - Mathematics

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Question

Examine the following function for continuity:

f (x) = x – 5

Sum

Solution

Let a be a real number, then,

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

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

Also f(a) = a - 5

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

Hence, the given function f(x) = (x - 5) is continuous.

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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 3.1 | Page 159

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