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Question
Let f(x)= |cosx|. Then, ______.
Options
f is everywhere differentiable
f is everywhere continuous but not differentiable at n = nπ, n ∈ Z
f is everywhere continuous but not differentiable at x = `(2"n" + 1) pi/2, "n" ∈ "Z"`
None of these
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Solution
Let f(x)= |cosx|. Then, f is everywhere continuous but not differentiable at x = `(2"n" + 1) pi/2, "n" ∈ "Z"`.
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