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Question
Prove that the following function do not have maxima or minima:
g(x) = logx
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Solution
Given function g(x) = log x
∴ g'(x) = `1/x, x > 0`
`g (x) = 1/x ne 0` for all x ∈ (0, ∞)
⇒ x ∈ R, g'(x) is never equal to zero.
Hence there is no highest or lowest value of g.
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