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Write an Example of a Function Which is Everywhere Continuous but Fails to Differentiable Exactly at Five Points. - Mathematics

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Question

Write an example of a function which is everywhere continuous but fails to differentiable exactly at five points.

Answer in Brief

Solution

\[f\left( x \right) = \left| x \right| + \left| x + 1 \right| + \left| x + 2 \right| + \left| x + 3 \right| + \left| x + 4 \right|\]

The above function is continuous everywhere but not differentiable at x = 0, 1, 2, 3 and 4

 

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Chapter 10: Differentiability - Exercise 10.2 [Page 16]

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RD Sharma Mathematics [English] Class 12
Chapter 10 Differentiability
Exercise 10.2 | Q 8 | Page 16

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