x²-2xy-2x+y²+2y+1

x-y/x²÷x²-2xy+y²/xy*（xy-x²） 【(1)/(x-y)+(1)/(x-y)】÷(2x)/(x²-2xy+y²) 计算3x[xy-2x(1/y-x/3]+3y(x²-y²) 计算：x²+2xy+y²/xy-y².x²-2xy+y²/xy+y&# 因式分解xy²-2xy+x+2y-1 多项式因式分解 1,(x-y)³-(x-y)²(x+y) 2,x(x²-xy)-(4x&# (x+y-2xy)(x+y-2)+(1-xy)² (-x-2y)(x²-2xy+4y²) x²-xy-2y²-x-y 因式分解 x³y-2x²y²+xy³ 化简：[(x+y)²-(x-y)²]÷2xy 若x=1/2,y=1 求x(x²+xy+y²)-y(x²+xy+y²)+3xy(