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Find all points of discontinuity of f, where f is defined by f(x)={|x|xifx≠00ifx=0 - Mathematics

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Question

Find all points of discontinuity of f, where f is defined by `f(x) = {(|x|/x , if x != 0),(0, if x = 0):}`

Sum

Solution

`f(x) = abs x/x, if  x ne 0` is not equal to 0, if x = 0

`lim_(x -> 0^-) f(x) = lim_(x -> 0^-) abs x/x`

= `lim_(h -> 0) abs (0 - h)/(0 - h)`

= `lim_(h -> 0) h/-h = -1`

`h -> 0`

`lim_(x -> 0^+) f(x) = lim_(x -> 0^+) abs x/x`

= `lim_(h -> 0) abs (0 + h)/(0 + h)`

= `lim_(h -> 0) h/h = 1`

Hence, f is not continuous at x = 0.

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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 8 | Page 159

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