已知:6x²-7xy-3y²+14x+y+a=(2x-3y+b)(3x+y+1)求a,b的值
已知:6x²-7xy-3y²+14x+y+a=(2x-3y+b)(3x+y+1)求a,b的值
x²(x+y)(y-x)-xy(x+y)(x-y) 已知a+b=4,ab=-2,求多项式3a²b+3
已知A=2x²+3xy-2x-1,B=-x²+xy-1,3A+6B的值与x无关,求y
已知:A=X*X-3xy+y*y,B=2x*x+xy-3y*3y.求A+B,A-B,A+2B
已知2x²+xy=a,3y²+2xy=b,求4x²+8xy+9y²的值(用a,b
已知2x²+xy=a,3y²-2xy=b,求4x²+8xy-9y²的值(用含a,
已知A=x²-2xy+y,B=x²+2xy+y²-3,求2A-[B-(B-A)+2A+B]
已知6x^2-7xy-3y^2+14x+y+a=(2x-3y+b)(3x+y+c),则……
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
已知A=3x²y-xy²,B=xy-3x²y,且|x-1|+(y+3)²=0,求
已知|x-y-3|+(a+b+4)²=0,求2a+2b-(a+b)分之(x-y)²-3(y-x)的值