=a定係-a
要有合理的解釋
答案不可a和-a
更新1:
但係^2同√約左會係 -a
數學的複雜問題
回答 (3)
2006-11-10 4:56 am
The answer is ( a )
Because (-a)^2 = -a x -a = a^2 ( - - = + )
e.g. (-2)^2 = -2 x -2 = 2^2 = 4 and then √4 = 2
or (-3)^2 = -3 x -3 = 3^2 = 9 and then √9 = 3
un
Because (-a)^2 = -a x -a = a^2 ( - - = + )
e.g. (-2)^2 = -2 x -2 = 2^2 = 4 and then √4 = 2
or (-3)^2 = -3 x -3 = 3^2 = 9 and then √9 = 3
un
2006-11-10 4:45 am
［(－ａ)^2］
=(-a)(-a)
=a^2
補回開方
√［(ａ)^2］
答案自然等於a
雖然x^2=9
x=3 or x=-3
但不適用於此情況
若問x=9的開方，x仍是等於3。
=(-a)(-a)
=a^2
補回開方
√［(ａ)^2］
答案自然等於a
雖然x^2=9
x=3 or x=-3
但不適用於此情況
若問x=9的開方，x仍是等於3。
2006-11-10 4:44 am
(-a)^2
=(-a)(-a)
=a
2006-11-09 20:45:16 補充：
=a^2
=(-a)(-a)
=a
2006-11-09 20:45:16 補充：
=a^2
收錄日期: 2021-04-20 20:33:37
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20061109000051KK03915