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Show that the function f defined by f(x) = ,,{xsin 1x,x≠00,x=0 is continuous at x = 0. - Mathematics

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Question

Show that the function f defined by f(x) = `{{:(x sin  1/x",", x ≠ 0),(0",", x = 0):}` is continuous at x = 0.

Sum
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Solution

Left hand limit at x = 0 is given by

`lim_(x -> 0^-) "f"(x) = lim_(x -> 0^-) x sin  1/x` = 0  ....`["since", -1 < sin  1/x  < 1]`

Similarly `lim_(x -> 0^+) "f"(x) = lim_(x -> 0^+) x sin  1/x` = 0.

. Moreover f(0) = 0.

Thus `lim_(x -> 0^-) "f"(x) = lim_(x -> 0^-) "f"(x)`

= f(0)

Hence f is continuous at x = 0.

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Chapter 5: Continuity And Differentiability - Solved Examples [Page 92]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 5 Continuity And Differentiability
Solved Examples | Q 4 | Page 92

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