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Show that the function defined by f(x) = |cos x| is a continuous function.

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Question

Show that the function defined by f(x) = |cos x| is a continuous function.

Sum
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Solution

It is known that f(x) = |cos x|

Let x = c ∈ R

`lim_(x -> c)` f(x) = `lim_(x -> c)` |cos x| = |cos c|

f(c) = |cos c|

Hence, f is a continuous function on x = c ∈ R.

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Chapter 5: Continuity and Differentiability - Exercise 5.1 [Page 161]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 5 Continuity and Differentiability
Exercise 5.1 | Q 32 | Page 161

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