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