數學~代數(加式)

👨🏻‍🏫 學術台數學

[匿名]

2012-09-23 10:37 pm

1.(4x+3+2y)(2y-3+4x)

回答 (4)

sioieng

2012-09-23 10:50 pm

✔ 最佳答案

1.

(4x + 3+ 2y)(2y - 3 + 4x)

= [(4x + 2y) + 3] [(4x + 2y) - 3]

= [4x + 2y]² - 3²

= [(4x)² + 2(4x)(2y) + (2y)²] - 9

= 16x² + 16xy + 4y² - 9

參考: sioieng

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Fai FAI

2012-09-28 12:00 am

1.(4x+3+2y)(2y-3+4x)

8xy-12x+16x^2+6y-9+12x+4y^2-6y+8xy

8xy+8xy+16x^2+4y^2+6y-6y+12x-12x-9

16xy+16x^2+4y^2-9

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HappySiu0

2012-09-24 2:12 am

1.(4x+3+2y)(2y-3+4x)
=8xy+6y+4y^2-12x-9-6y+16x^2+12x+8xy
=16xy+4y^2-9+16x^2

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用戶27207

2012-09-23 10:42 pm

Hint: (a + b)(a - b) = a² - b².

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