求式！！
求下列 △ABC 的周界。 ( 答案準確至 3 位有效數字 )
1. A ( -2 , 3 ) , B ( -2 , -3 ) , C ( 3 , 0 )
( 答案 = 17.7 )
2. A ( 1 , 1 ) , B ( 6 , 2 ) , C ( 3 , 5 )
( 答案 = 13.8 )
F.3 MATH (直角坐標幾何)
2009-11-25 6:08 am
回答 (1)
2009-11-25 6:14 am
✔ 最佳答案
(1) AB = 3 - (-3) = 6AC = √[(-2-3)^2 + (3 - 0)^2] = √(25+9) = 5.83
BC = √[(-2-3)^2 + (-3 - 0)^2] = √(25+9) = 5.83
周界 = 6 + 5.83 + 5.83 = 17.7
(2) AB = √[(1-6)^2 + (1-2)^2] = √(25+1) = 5.10
AC = √[(1-3)^2 + (1-5)^2] = √(4+16) = 4.47
BC = √[(6-3)^2 + (2-5)^2] = √(9+9) = 4.24
周界 = 5.10 + 4.47 + 4.24 = 13.8
收錄日期: 2021-04-23 23:21:36
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20091124000051KK01454