3xy(-2x)³(-1/4y²)²=
(-2/3X³y+4x²y²-1/2xy²)/(-xy/4) 急
去括号:1/2(2X²Y-3XY²+4XY-X²Y²)=?
3x²y+xy²-[2xy²-4x²y+(x²y-2xy²)
2xy-1/2(4xy-8x²y²)+2(3xy-5x²y²),其中x=3/2,
已知x-2y=3,x²-2xy+4y²=11,求下列各值; (1)xy (2)x²-2xy
化简并求值 xy-2{xy-[3x²y-(xy²+0.5xy)]+4x²y},其中x=1,
已知2X-3√xy-2y=0(x>0)求2x²+xy-9y²分之x²+4xy-16y
(1).设A=2X²-3Xy+y²+X-3y,B=4X²-6xy+2y²+4X-
|x+2|+(y-1/4)²=0,求2(x²y+xy)-3(x²y-xy)-4x²
计算 2xy[4x²y²-3y(xy+x²y)-xy²]
已知x²-3xy+4x=3,y²+xy-4y+7=0,则xy-1/2(x²+y²
已知A=x³-2y³+3x²y+xy²-3xy+4,B=y³-x