因式分解問題!!thx x1000

🎓 學業台小學及中學教育

用戶11093

2008-10-22 3:32 am

因式分解 44x 2次方-220xy+275y 2次方

點計???長細解答!!thx X100000000800000000789

更新1:

因式分解 -12x 2次方+36xy-27y 2次方點計???

回答 (3)

wing

2008-10-28 12:50 am

✔ 最佳答案

44x 2次方-220xy+275y 2次方=44x^2-220xy+275y^2

=275y^2-220xy+44x^2
=11(25y^2-20xy+4x^2)....抽公因式
=11[(5y)^2-2(5y)(2x)+(2x)^2].....用(a-b)^2= a^2-2ab+b^2
=11(5y-2x)^2

-12x 2次方+36xy-27y 2次方=-12x^2+36xy-27y^2

=-3(4x^2-12xy+9y^2)....抽公因式
=-3[(2x)^2-2(2x)(3y)+(3y)^2].....用(a-b)^2= a^2-2ab+b^2
=-3(2x-3y)^2

參考: 會考數學c既人~

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[匿名]

2008-10-24 6:07 am

44x2-220xy+275y2
=11(4x2-20xy+25y2)
=11(2x-5y)2
12x2+36xy-27y2
=12x2+36xy+(-27y2)
=3[4x2+12xy+(-9y2)]
=3[2x+(-3y)]2
=3(2x-3y)2

參考: 自己

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