xy²-2xy+2y-4 怎么化简

xy²-2xy+2y-4 怎么化简 计算：4xy²-3x²y-{3x²y-[2xy²-4x²y+2(x²y-2xy²)]急 因式分解xy²-2xy+2y-4 分解因式xy²-2xy+2y-4 分解因式:xy²-2xy+2y-4 x²-4y²/x²+2xy+y²÷x+2y/2x²+2xy 6x²-xy-15y²=0 求x²-2xy+4y²/2x²-3xy-3y²告诉下 6x²-xy-15y²=0 求2x²-3xy-3y²分之x²-2xy+4y² x²-2xy+y²-9 已知2x²-3y²=xy,(xy≠0),求值（4xy-x²）／(xy+2y²)的值 1 3x²+4xy-y²=2 4xy+1-4x²-y²= 已知x² -XY = 2,Y² -XY= 5,求x² - 4x Y+ Y² = 2x² + xY -3Y² = x² 已知x² -XY = 2,Y² -XY= 5,求x² - 4x Y+ Y² = 2x² + xY -3Y² = x² + xY- 2Y² =求x² - 4x Y+ Y² = 单项式2xy,6x²y²,-3xy,-4x²y²的和为-------------- 求单项式2xy,6x² y²,-3xy,-4x²y²的和. 计算x²-x/x²×x/1-x和x²-4y²/x²+2xy+y²÷x+2y/x²+xy 已知x²+xy=3,xy+y²=—2,求x²-y²的值?x²+4xy+3y²的值?2x²-xy-3y 已知x-2y=3,x²-2xy+4y²=11,求①xy ②x²y-2xy² 整式乘法..1.3xy（x²y-xy²+xy）-xy²（2x²-xy+2x）2.（x-1）（x²-4x+3）-x（x²-5x+2)