The number of diagonals that can be drawn in a regular polygon wi_英语解答

The number of diagonals that can be drawn in a regular polygon with
21:00前要,如果有算式要列算式!+_+
是The number of diagonals that can be drawn in a regular polygon withtwenty sides(icosagon) is___________.

人气：270 ℃　时间：2020-04-08 20:15:33

解答

一个正多边形内能画的对角线的数目
前提n>=3,正多边形对角线数目(n*(n-3))/2
*表示乘
OK?