Biggest Reuleaux Triangle inscribed within a square which is inscribed within a hexagon | Function to find the biggest reuleaux triangle ; side cannot be negative ; height of the reuleaux triangle ; area of the reuleaux triangle ; Driver code
< ? php function Area ( $ a ) { if ( $ a < 0 ) return -1 ; $ h = 1.268 * $ a ; $ A = 0.70477 * pow ( $ h , 2 ) ; return $ A ; } $ a = 5 ; echo round ( Area ( $ a ) , 4 ) ; ? >