(- 2/3xy)·(1/2 x)²
已知(x+1)²+|y-1|=0,求2(xy-5xy²)-(3xy²-xy)得值
下列多项式:(1)x²+xy-y²;(2)-x²+2xy-y²;(3)xy+x&
-3(2x²-xy)+4(x²+xy-6)
1-(3xy-x)+【-2(2x+3xy)】
计算3xy[2xy-x(y-2)+x-1]
化简求值3x²y-[2xy-2(xy-3/2x²y)+xy]+3xy²其中x=3、y=-1
化简并求值 xy-2{xy-[3x²y-(xy²+0.5xy)]+4x²y},其中x=1,
先化简,再求值 ⒈2(Xy+Xy)-3(Xy-xy)-4Xy,其中X=1,y=-1
因式分解x²-2xy-3x
1/2x²-1/3XY+XY-2/3x² 合并同类项
-3(xy-2x²)-[y²-(5xy-4x²)+2xy]
已知x:y=3:2,求(x²+3xy)/(xy+2xy)