立体几何中的最值问题在近年的高考试题中出现的频次较高,且常考常新.因为解决这类问题不仅要具备较强的空间想象能力,而且还要会灵活运用代数、几何、三角等相关知识.因而是一类既富思考情趣,又融众多知识和技巧于一体,综合性强、灵活性高、难度颇大的挑战性问题.它充分体现了变知识立意为能力立意,在知识网络交汇点处设计试题的高考命题指导思想,是考查学生数学能力和数学素养的极好素材,应引起我们足够的重视.下面结合具体例子谈谈这类 In the recent years, college entrance examination exams have the highest value problems and often test new ones, because solving such problems not only requires strong spatial imagination ability, but also makes full use of algebra, geometry, Trigonometry and other related knowledge.Therefore, it is a kind of challenging problem that is both rich in thinking and fun, and melting many knowledge and skills in one, comprehensive, flexible and difficult.It fully embodies the change of knowledge conception as ability conception, At the intersection of knowledge network design questions of the college entrance examination test guidelines, is to examine the students math ability and mathematical quality of the excellent material, should cause us enough attention .Considering specific examples to talk about such