Question Number 28367 by abdo imad last updated on 24/Jan/18
$${find}\:{F}\in{R}\left({x}\right)\:\:{wich}\:{verify}\:\:{F}\left({x}+\mathrm{1}\right)\:−{F}\left({x}\right)=\:\frac{{x}+\mathrm{3}}{{x}\left({x}−\mathrm{1}\right)\left({x}+\mathrm{1}\right)}. \\ $$