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Discuss the continuity of the function f, where f is defined by ,,,f(x)={3,if0≤x≤14,if1<x<35,if3≤x≤10 - Mathematics

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Question

Discuss the continuity of the function f, where f is defined by `f(x) = {(3, ","if 0 <= x <= 1),(4, ","if 1 < x < 3),(5, ","if 3 <= x <= 10):}`

Sum

Solution

`f(x) = {(3, ","if 0 <= x <= 1),(4, ","if 1 < x < 3),(5, ","if 3 <= x <= 10):}`

For `0 le x le 1`, f(x) = 3;

1< x < 3, f(x) = 4 and

`3 < x le 10,` f(x) = 5, is a continuous function

So this is a function

At x = 1,

`lim_(x -> 1^-) f(x) = lim_(x -> 1^-)` (3) = 3

`lim_(x -> 1^+)  f(x) = lim_(x -> 1^+)` (4) = 4

Hence, f is not continuous at x = 1.

At x = 3,

`lim_(x -> 3^-) f(x) = lim_(x -> 3^-)` (4) = 4

`lim_(x -> 3^+) f(x) = lim_(x -> 3^+)` (5) = 5

Hence, f is not continuous at x = 3.

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Chapter 5: Continuity and Differentiability - Exercise 5.1 [Page 160]

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NCERT Mathematics [English] Class 12
Chapter 5 Continuity and Differentiability
Exercise 5.1 | Q 14 | Page 160

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