x^2-2xy+y^2+3x-3y+2 x^2+(a+1)x-(6a^2-13a+6) 　x＾2＋xy－2y＾2＋2x＋

x^2-2xy+y^2+3x-3y+2 =(x-y)^2+3(x-y)+2=(x-y+2)(x-y+1)x^2+(a+1)x-(6a^2-13a+6)=x^2+(a+1)x-(3a-2)(2a-3)=(x+3a-2)(x-2a+3)x＾2＋xy－2y＾2＋2x＋7y－3X=(x+2y)(x-y)+2(x+2y)+3y-3x=(x+2y)(x-y)+3(y-x)=(x+2y-3)(x-y)