Question Number 35050 by math khazana by abdo last updated on 14/May/18
$${calculate}\:\sum_{{n}=\mathrm{0}} ^{\infty} \:\:\:\frac{\left(−\mathrm{1}\right)^{{n}} \:\:{x}^{\mathrm{2}{n}+\mathrm{1}} }{\mathrm{4}{n}^{\mathrm{2}} −\mathrm{1}} \\ $$
calculate-n-0-1-n-x-2n-1-4n-2-1-