Question

在实数范围内因式分解x^2-4xy+3y^2-4x+10y+3和x^2+xy-2y^2+2x+7y-3

在线等，快快！！！！！！！！！！！！！！！！！！！！！！！

Answer 1

x^2-4xy+3y^2-4x+10y+3
=（x-y)(x-3y)-4x+10y+3
=(x-y-3)(x-3y-1)

x^2+xy-2y^2+2x+7y-3
=(x-y)(x+2y)+2x+7y-3
=(x-y+3)(x+2y-1)

追问

（x-y)(x-3y)-4x+10y+3到(x-y-3)(x-3y-1)，(x-y)(x+2y)+2x+7y-3到(x-y+3)(x+2y-1)怎么来的

追答

十字相乘法
x-y -3 x-y 3
╳ ╳
x-3y -1 x+2y -1
(x-y-3)(x-3y-1) (x-y+3)(x+2y-1)

追问

再详细些，列个式子，我数学比较差

追答

十字相乘法
x-y -3 x-y 3
╳ ╳
x-3y -1 x+2y -1

(x-y-3)(x-3y-1) (x-y+3)(x+2y-1)
这就是列的式子

Answer 2

6X^2-7xy-3y^2-x+7y-2 =6x^2-(7y+1)x-(3y^2-7y+2) =6x^2-(7y+1)x-(y-2)(3y-1) =[2x-(3y-1)][3x+(y-2)] =(2x-3y+1)(3x+y-2) 很不错哦，你可以试下
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