Interesting Maths Q1 (Hard)
2011-11-02 6:16 pm
Here's a right rectangular pyramid, with 2x length, 3x width and x height. Find the angle between two slant sides.
回答 (4)
2011-11-11 9:52 pm
✔ 最佳答案
令x=2, pyramid V-ABCD, AB=6, BC=4,取坐標系: A(0,0,0), B(6,0,0), D(0,4,0), C(6,4,0), V(3,2,2)
ABV平面方程式為 y-z=0
BCV平面方程式為 2x+3z=12
(0, 1, -1) ∙ (2, 0, 3) = √2 √13 cost
cost = -3/√26
t= π-arccos((3/√26)
2011-11-11 13:52:30 補充：
t= π-arccos(3/√26)
2011-11-11 13:54:10 補充：
大約126.04度
2011-11-03 3:01 pm
自由自在is right
2011-11-03 5:54 am
The answer is not correct. If AE is perpendicular to VB, but CE is not perpendicualr to VB.
2011-11-02 7:10 pm
圖片參考：http://i1191.photobucket.com/albums/z467/robert1973/Nov11/Crazygeom3.jpg
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參考: Myself
收錄日期: 2021-04-13 18:20:09
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20111102000051KK00186