初中數學.................

2007-12-03 6:07 am

1.x(6)-x(4)
=??
2.y²-x²-2xy-2y²
=??

回答 (6)

2007-12-03 7:42 am

✔ 最佳答案

1.x^6-x^4
=x^6-x^4(x^6和x^4是異類項，不能相減)

2.y²-x²-2xy-2y²
=-x^2-2xy-y^2
=(-x-y)(x+y)
= -(x+y)(x+y)
= -(x+y)^2

參考: me

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2007-12-04 10:24 am

1.x(6)-x(4)
=(x 2次-1)(x4次 )

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2007-12-03 6:22 am

1 6x - 4x =2x or
6x - 4x = 0
2x= 0
x = 1/2
2 y²-x²-2xy-2y²
= -x²-2xy-y²
= (-x+y) (x-y)

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2007-12-03 6:18 am

1. x(6)-x(4)=6x-4x
=2x

2. y²-x²-2xy-2y²=-x²-2xy-y²
=-(x²+2xy+y²)
=-(x+y)²

參考: 自己

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2007-12-03 6:16 am

1)

6x - 4x

= 2x

2) y²-x²-2xy-2y²

= y² - 2y² - x² - 2xy

= y² - x² - 2xy

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2007-12-03 6:10 am

1.6x-4x
=2x

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