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The Function F (X) = 1 + |Cos X| is - Mathematics

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Question

The function f (x) = 1 + |cos x| is

Options

  • continuous no where

  • continuous everywhere

  •  not differentiable at x = 0

  • not differentiable at x = n π, n ∈ Z

MCQ
Answer in Brief
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Solution

(b) continuous everywhere
Graph of the function f (x) = 1 + |cos x| is as shown below:

From the graph, we can see that f (x) is everywhere continuous but not differentiable at

\[x = \left( 2n + 1 \right)\frac{\pi}{2}, n \in Z\]
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Chapter 10: Differentiability - Exercise 10.4 [Page 19]

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RD Sharma Mathematics [English] Class 12
Chapter 10 Differentiability
Exercise 10.4 | Q 18 | Page 19

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