Question Number 134093 by mohammad17 last updated on 27/Feb/21
$${where}\:{is}\:{the}\:{function}\:{derivable}\: \\ $$$$ \\ $$$${f}\left({z}\right)={zRez}+\overset{−} {{z}imz}+\overset{−} {{z}} \\ $$$$ \\ $$$${help}\:{me}\:{sir}\:{please} \\ $$
where-is-the-function-derivable-f-z-zRez-z-imz-z-help-me-sir-please-