MCQ
Let $f(x) = e^x - e^{-x} + cosx$, then $f(x)$ is 
  • always increasing
  • B
    always decreasing
  • C
    non differentiable at $x = 0$
  • D
    local maxima at $x = 1.$

Answer

Correct option: A.
always increasing
a
$f'(x) = (e^x - e^{-x}) - sinx$
alwasys positive and three an increasing function.

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