solve the following equation:
x^2 + (x-2)^2 = 8.............
one ~equation
2012-08-25 5:48 am
回答 (2)
2012-08-25 5:57 am
✔ 最佳答案
x^2 + (x-2)^2 = 82x^2 -4x -4 = 0
x^2 -2x -2 = 0
x = 1+/-(3)^1/2
= 1+sq.rt(3) or 1-sq.rt(3)
2012-08-25 07:16:51 補充：
For 002,
(sb)(sb) 2
x(x-2)= (-----)x
(sb)(sb) x
x^2-2 = 2 <---------------呢一步錯左,應該係x^2-2x=2
x^2-2+2 = 2+2
x^2 = 4
x = 2
參考: 神風亨
2012-08-25 6:26 am
x^2 + (x-2)^2 = 8
x^2+(x)^2-2(x)(-2)+(-2)^2 =8
x^2+x^2-4x+4=8
x^2+x^2-4x+4-4=8-4
2x^2-4x=4
2x(x-2)=4
2x(x-2)(sb)4
--------- = -------
2x (sb)(sb) 2x
(sb)(sb) 2
x-2 = --------
(sb)(sb) x
(sb)(sb) 2
x(x-2)= (-----)x
(sb)(sb) x
x^2-2 = 2
x^2-2+2 = 2+2
x^2 = 4
x = 2
(sb)只為隔位之用
x^2+(x)^2-2(x)(-2)+(-2)^2 =8
x^2+x^2-4x+4=8
x^2+x^2-4x+4-4=8-4
2x^2-4x=4
2x(x-2)=4
2x(x-2)(sb)4
--------- = -------
2x (sb)(sb) 2x
(sb)(sb) 2
x-2 = --------
(sb)(sb) x
(sb)(sb) 2
x(x-2)= (-----)x
(sb)(sb) x
x^2-2 = 2
x^2-2+2 = 2+2
x^2 = 4
x = 2
(sb)只為隔位之用
參考: 自己
收錄日期: 2021-04-13 18:55:59
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https://hk.answers.yahoo.com/question/index?qid=20120824000051KK00760