81(a+b)²-4(a-b)² 2x³y+8x²y²+8xy
已知2x²+xy=a,3y²+2xy=b,求4x²+8xy+9y²的值(用a,b
已知A=2x²+3xy-y²,B=-1/2xy,C=1/8x³y³-1/4x
已知2x²+xy=a,3y²-2xy=b,求4x²+8xy-9y²的值(用含a,
x²(x+y)(y-x)-xy(x+y)(x-y) 已知a+b=4,ab=-2,求多项式3a²b+3
A=2x²-3xy+y²-x+2y,B=4x²-6xy+2y²+3x-y,若x=
设A=2x²-3xy+y²-x+2y,B=4x²-6xy+2y²-3x-y,若x
(1)16-(2a+3b)²(2)-36x²+12xy-y²(3)4x(a-b)-8y(b
因式分解2x²y-xy-3y (-a+b)+c²(a-b)
若A=2x²-4xy-2y²-2x+2y,B=4x²-6xy+2y²-3x-y.
1.设A=2x²-3xy+y²+x-3y,B=4x²-6xy+2y²+4x-y,
设A=2x²-3xy+y²+x-3y ,B=4x²-6xy+2y²+4x-y ,
设A=2X²-3xy+y²-x+2y,B=4x²-6xy+2y²-3x-y,若|