求证： n 棱柱中过侧棱的对角面的个数是f(n)=12n(n-3) ．_刷题宝

题干

求证： n 棱柱中过侧棱的对角面的个数是f(n)=

1

2

n(n-3) ．

上一题下一题 0.0难度选择题更新时间:2018-04-02 08:59:27

答案(点此获取答案解析）

【解答】证明：①当 n=4 时，四棱柱有 2 个对角面：

1

2

×4×(4-3)=2 ，命题成立．②假设 n=k

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King's College Summer School is anannual(每年的) training program for high school students at all levels who want to improvetheir English. Courses are given by the teachers of King's College and other colleges in New York. Trips to museums and culture centres are also organized.This year's summer school will be from July 25 to August 15. More informationis as follows:

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Please write to: Thompson, Sanders 1026 King's Street, New York, USA

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