if-ABC-is-a-triangle-with-usual-notations-then-prove-the-following-inequality-4R-r-3-4r-2-2R-r-3s-2-2R-r-0-

Question Number 164156 by HongKing last updated on 14/Jan/22

if ABC is a triangle with usual

notations, then prove the following

inequality :

{(4 R + r)}^{3} - {4 r}^{2} (2 R - r) - {3 s}^{2} (2 R + r) ⩾ 0