当x=3,y=-1/3时,求多项式3x²y-[2xy²-2(xy-3/2x²y)+xy]+
求多项式2x²-3xy+y²-2xy-2x²+5xy-2y+1的值,其中x=22/7,y=
已知x/y=3,求x²+2xy-3y²/x²-2xy+y²
已知x/y=3,求x²+2xy-3y²/x²-xy+y²的值
x/y=2,求分式x²-xy+3y²/x²+xy+6y²
|x+2y+3|+(2x+y)²=0求x²-xy+y²
已知X²-5XY+6Y²=0,求(X²+3XY)\2Y²的值
计算:(1).(-2xy²)*(3x²y)²
已知x/y=3,求x²+2xy-3y²/x²-xy+y³的值
当k=_______时,多项式x²-2kxy-3y²-xy+8中不含有xy项
已知x-2y=3,x²-2xy+4y²=11,求①xy ②x²y-2xy²
已知|x+2|+(y+1²=0,求x²+(2xy-3y²)-2(x²+xy-2y
已知3x²+xy-2y²=0.求代数式y分之x-x分之y-xy分之x²+y²的值