請證明如果x^2=y^2，x一定等如y
回答 (4)
2010-09-05 4:16 am
✔ 最佳答案
x^2 -y^2=0(x+y)(x-y)=0
x= -y or "x=y"
x一定等如y
2010-09-05 2:38 am
which mean we hv
x^2=y^2
x=y or x= -y
2010-09-04 18:39:18 補充：
remarks: not only 1 answer
x^2=y^2
x=y or x= -y
2010-09-04 18:39:18 補充：
remarks: not only 1 answer
2010-09-05 2:31 am
根本就不等於的，舉個反例：
5^2 = (-5)^2
5 = -5 ???
5^2 = (-5)^2
5 = -5 ???
收錄日期: 2021-04-13 17:29:35
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