求一個13邊型,裡面隨機選3個點連成一個三角型,可以連成幾個直角三角形?
回答 (1)
2017-04-01 8:19 am
3繳型123 = 1 個
4繳型1234 = 123.124 + 234 = 2 + 1 = 3 個
5邊形12345 = 123. 124. 125 + 234. 235 + 345 = 3 + 2 + 1 = 6 個
......
13 邊形 = 11 + 10 + 9 + ...+ 1 = 11 * 12 / 2 = 66 個
4繳型1234 = 123.124 + 234 = 2 + 1 = 3 個
5邊形12345 = 123. 124. 125 + 234. 235 + 345 = 3 + 2 + 1 = 6 個
......
13 邊形 = 11 + 10 + 9 + ...+ 1 = 11 * 12 / 2 = 66 個
收錄日期: 2021-04-30 19:56:05
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https://hk.answers.yahoo.com/question/index?qid=20170331130236AAjLpli