内角是任何形状的里面角度,比如三角形的内角是60°
正八边形:n=8 [ (n-2) x 180° ] / n =[ (8-2) x 180° ] / 8 =1080° / 8 =135°
正六边形:n=6
[ (n-2) x 180° ] / n
=[ (6-2) x 180° ] / 6
=720° / 6
=120°