Question Number 29851 by abdo imad last updated on 13/Feb/18
$${let}\:{give}\:{f}\left({z}\right)=\frac{{tanz}\:−{z}}{\left(\mathrm{1}−{cosz}\right)^{\mathrm{2}} }\:\:{find}\:{Res}\left({f},\mathrm{0}\right). \\ $$
let-give-f-z-tanz-z-1-cosz-2-find-Res-f-0-