Question

can coshx ever be negative
? if yes or no why?

Answer 1

\[\cosh x = \frac {e^x + e^{-x}} {2} = \frac {e^{2x} + 1} {2e^x} = \frac {1 + e^{-2x}} {2e^{-x}}\]

Answer 2

you can work it from there