Question Number 95941 by mathmax by abdo last updated on 28/May/20
$$\mathrm{prove}\:\mathrm{that}\:\frac{\mathrm{1}}{\mathrm{sinx}}\:=\sum_{\mathrm{n}=−\infty} ^{+\infty} \:\frac{\left(−\mathrm{1}\right)^{\mathrm{n}} }{\mathrm{x}+\mathrm{n}\pi} \\ $$