化简求值:3x2y2+2xy-7x2y2-32
化简并求值:(2x2y-2xy2)-[(-3x2y2+3x2y)+(3x2y2-3xy2)],其中x=−12,y=2
化简求值(2X2-2y2)-3(X2y2+X2)+3(X2y2+y2),其中X=-1,y=2
化简求值:[x(x2y2-xy)-y(x2-x3y)]÷3x2y,其中x=3,y=-1.
多项式x5y2+2x4y3-3x2y2-4xy是( )
先化简,再求值:(-3xy)2(x2+xy-y2)-3x2y2(3x2+3xy+y2),其中x=-43
化简:[(xy-2)(xy+2)-2x2y2+4]÷(xy).
计算:[6xy2(x2-3xy)-(-3x2y3)]÷(3x2y2)
已知x-y=l,xy=2,求x3y-2x2y2+xy3的值.
计算:[x(x2y2-xy)-y(x2+x3y)]÷3x2y.
计算:[x(x2y2-xy)-y(x2-x3y)]÷3x2y.
已知x-y=1/xy=3.求x3次方y-2x2y2+xy3
已知x+y=4,xy=2,则x3y+x2y2+xy3的值: