化简(4x²-5xy)-(1/3y²+2x²)+2(3xy-1/4y²-1/12
3x²y+xy²-[2xy²-4x²y+(x²y-2xy²)
2xy-1/2(4xy-8x²y²)+2(3xy-5x²y²),其中x=3/2,
计算 2xy[4x²y²-3y(xy+x²y)-xy²]
去括号:1/2(2X²Y-3XY²+4XY-X²Y²)=?
(-2/3X³y+4x²y²-1/2xy²)/(-xy/4) 急
4x²y-1/2{x²y-[5x²y-2(2xy²+1/4xy)]}+3xy
化简3/(x²+2xy+y²)-4/(x²-2xy+y²)+5/(x²
已知x-2y=3,x²-2xy+4y²=11,求下列各值; (1)xy (2)x²-2xy
化简(3X²-XY+Y²)-5(X²-XY+2Y²)
化简求值 已知:(x+2)2;+|y+1|=0求5xy²-{2xy²-[3xy²(4xy&
化简 (x+y)(x²-xy+y²) ; 3(2x-1)(x+6)-5(x-3)(x+6)
化简并求值 xy-2{xy-[3x²y-(xy²+0.5xy)]+4x²y},其中x=1,