Question Number 32891 by mondodotto@gmail.com last updated on 05/Apr/18
Commented by Tinkutara last updated on 05/Apr/18
It is wrong.
Commented by Joel578 last updated on 05/Apr/18
$$\mathrm{sec}\:{x}\:=\:\frac{\mathrm{1}}{\mathrm{cos}\:{x}} \\ $$
Commented by mrW2 last updated on 06/Apr/18
$$\mathrm{sec}^{−\mathrm{1}} {x}\neq\left(\mathrm{sec}\:{x}\right)^{−\mathrm{1}} \\ $$$$\mathrm{sec}^{−\mathrm{1}} {x}={arcsec}\:{x} \\ $$$$\left({sec}\:{x}\right)^{−\mathrm{1}} =\frac{\mathrm{1}}{\mathrm{sec}\:{x}}=\mathrm{cos}\:{x} \\ $$