有过程4x²-(4x²-4xy+y²)=
已知x²+y²-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
分式除法(2y-x)÷x²-4xy+4y²/x+3xy要过程
3x²y+xy²-[2xy²-4x²y+(x²y-2xy²)
已知有理数x,y满足xy=4,x+y=7,则x²y+xy²=()?
已知2x+y=0,求x-2y/x²+xy*(x²-y²)/x²-4xy+4y
x²+xy/(x-4y)(x+y),其中x=4,y=-1
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
计算 2xy[4x²y²-3y(xy+x²y)-xy²]
4x²+8xy=y²+xy,求x:y=?
已知x²+y²-2x+4y+5=0,求X^4-y^4/2x^2+xy-y²·2x-y/xy
(-x-2y)(x²-2xy+4y²)
已知X²+Y²+X²Y²-4XY+1=0 求:(X-Y)^2008-(XY)^2