Question Number 180623 by cortano1 last updated on 14/Nov/22
Answered by HeferH last updated on 14/Nov/22
$$\left({R}\:+\:{r}\right)^{\mathrm{2}} =\:{r}^{\mathrm{2}} \:+\:\mathrm{4}{r}^{\mathrm{2}} \\ $$$$\:\frac{\mathrm{2}{r}}{{R}}\:=\:\frac{\mathrm{1}\:+\:\sqrt{\mathrm{3}}}{\mathrm{2}} \\ $$$$\: \\ $$