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Question
Show that the function defined by f(x) = |cos x| is a continuous function.
Solution
It is known that f(x) = `abs (cos x)`
Let x = c `in` on R.
`lim_(x -> c) f(x) = lim_(x -> c) abs (cos x) = abs (cos c)`
f(c) = `abs (cos c")`
Hence, f is a continuous function on x = c `in` R.
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