HMMT 二月 2000 · GEN 赛 · 第 21 题
HMMT February 2000 — GEN Round — Problem 21
题目详情
- Find the area of the six-p oin ted star if all edges are of length s , all a ute angles are 60 Æ and all obtuse angles are 240 .
解析
- It is lear that w e an split the gure in to 12 equilateral triangles, all of whi h ha v e side p p 2 s 3 2 length s . So, sin e the area of one of these triangles is , the total area is 3 s 3 . 4 p p 2 A eq 1 4 p 3