谢谢（关于因式分解）2x²+xy-y²-4x+5y-6x²-2x-14(x-y+1)+y(

2x²+xy-y²-4x+5y-6=(2x-y)(x+y)-4x+5y-6=(2x-y+2)(x+y-3)
x²-2x-1=(x-1)²-2=(x-1-√2)(x-1+√2)
4(x-y+1)+y(y-2x)=y²-4y+4+4x-2xy=(y-2)²+2x(y-2)=(2x+y-2)*(y-2)
3x²+5xy-2y²+x+9y-4=(3x-y)(x+2y)+x+9y-4=(3x-y+4)(x+2y-1)
x³-3x²+4=(x+1)(x²-4x+4)=(x+1)(x-2)²

问几道题 1. 1／4x五y－1／4xy五 五这个是5次方的意思 2. 4a二b二问几道题 1. 1／4x^5y－1／4xy^5 =1/4xy(x^4-y^4) =1/4xy(x