HMMT 二月 2001 · 团队赛 · 第 6 题
HMMT February 2001 — Team Round — Problem 6
题目详情
- What is the radius of the smallest sphere in which 4 spheres of radius 1 will fit?
解析
- What is the radius of the smallest sphere in which 4 spheres of radius 1 will fit? Solution: The centers of the smaller spheres lie on a tetrahedron. Let the points of the tetrahedron be (1 , 1 , 1), ( − 1 , − 1 , 1), ( − 1 , 1 , − 1), and (1 , − 1 , − 1). These points have distance √ √