Menu Close

Find-all-the-real-valued-f-satisfying-f-2x-f-2y-f-f-y-4x-8y-for-all-real-numbers-x-and-y-




Question Number 53842 by Tawa1 last updated on 26/Jan/19
Find all the real valued  f  satisfying                                f[2x + f(2y)] + f[f(y)]  =  4x + 8y  for all real numbers  x and y.
$$\mathrm{Find}\:\mathrm{all}\:\mathrm{the}\:\mathrm{real}\:\mathrm{valued}\:\:\mathrm{f}\:\:\mathrm{satisfying}\: \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\mathrm{f}\left[\mathrm{2x}\:+\:\mathrm{f}\left(\mathrm{2y}\right)\right]\:+\:\mathrm{f}\left[\mathrm{f}\left(\mathrm{y}\right)\right]\:\:=\:\:\mathrm{4x}\:+\:\mathrm{8y} \\ $$$$\mathrm{for}\:\mathrm{all}\:\mathrm{real}\:\mathrm{numbers}\:\:\mathrm{x}\:\mathrm{and}\:\mathrm{y}.\: \\ $$

Leave a Reply

Your email address will not be published. Required fields are marked *