求三點共線之數學問題解答
下列哪些點與A(6,2,-4) B(-3,5,8)兩點共線?
(1) (3,3,0)
(2) (0,4,4)
(3) (9,1,-8)
(4) (3,7,4)
(5) (-9,3,4)
求高手詳細解答謝謝!
回答 (2)
✔ 最佳答案
下列哪些點與A(6,2,-4),B(-3,5,8)兩點共線?
(1) (3,3,0)
(2) (0,4,4)
(3) (9,1,-8)
(4) (3,7,4)
(5) (-9,3,4)
Sol
(6+3):(2-5):(-4-8)
=9:-3:-12
=3:-1:-4
(1) (6-3):(2-3):(-4-0)
=3:-1:-4
(2) (6-0):(2-4):(-4-4)
=6:-2:-8
=3:-1:-4
(3) (6-9):(2-1):(-4+8)
=-3:1:4
=3:-1:-4
(4) (6-3):(2-7):(-4-4)
=3:-5:-8<>=3:-1:-4
(5) (6+9):(2-3):(-4-4)
=15:-1:-8=3:-1:-4
選(1),(2),(3)
(6+3):(2-5):(-4-8)=9:-3:-12=-3:1:4
(6-3):(2-3):(-4-0)=3:-1:-4=-3:1:4-----(1)
(6-0):(2-4):(-4-4)=6:-2:-8=-3:1:4-----(2)
(9-6):(1-2):(-8+4)=3:-1:-4=-3:1:4----(3)
(3-6):(7-2):(4+4)=-3:5:8--------------(4)
(-9-6):(3-2):(4+4)=-15:1:8-------------(5)
由以上知與A,B共線之點答案為(1)(2)(3)
收錄日期: 2021-05-02 12:09:47
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