Previous in Relation and Functions Next in Relation and Functions
Question Number 40896 by abdo.msup.com last updated on 28/Jul/18
$${for}\:\mid{x}\mid<\mathrm{1}\:{prove}\:{that} \\ $$$$\frac{\mathrm{1}}{\sqrt{\mathrm{1}−{x}^{\mathrm{2}} }}\:=\sum_{{n}=\mathrm{0}} ^{\infty} \:\frac{{C}_{\mathrm{2}{n}} ^{{n}} }{\mathrm{4}^{{n}} }\:{x}^{\mathrm{2}{n}} \\ $$