Question Number 1862 by 123456 last updated on 17/Oct/15
$${f}\left[{x}−{f}\left({y}\right)\right]={f}\left({x}\right)−{f}\left({y}\right),\forall\left({x},{y}\right)\in\mathbb{R} \\ $$$${f}:\mathbb{R}\rightarrow\mathbb{R} \\ $$$${f}\left({x}\right)=? \\ $$
Answered by prakash jain last updated on 18/Oct/15
$${f}\left({x}\right)={x}\:\mathrm{is}\:\mathrm{one}\:\mathrm{solution}. \\ $$$$ \\ $$
Answered by Rasheed Soomro last updated on 19/Oct/15
$${More}\:{generally}\:{f}\left({x}\right)={x}+{c}\:\:{is}\:\:{a}\:\:{solution},{where}\:{c}\:{is}\:{a}\:{constant}. \\ $$