已知|xy-4|+(x-2y-2)²=0
已知2x+y=0,求x-2y/x²+xy*(x²-y²)/x²-4xy+4y
已知X²+Y²+X²Y²-4XY+1=0 求:(X-Y)^2008-(XY)^2
已知x²+y²-2x+4y+5=0,求(x²-xy)分之y减去(xy-x²)分之
已知x²+y²-4x-2y+5=0,求代数式[(√x-√y)²+4√xy]/(x+√xy)
已知:x²+y²-4x-2y+5=0,求x+√xy分之(√x-√y)²+4√xy的值.
已知x²+y²-2x+4y+5=0,求X^4-y^4/2x^2+xy-y²·2x-y/xy
已知2X-3√xy-2y=0(x>0)求2x²+xy-9y²分之x²+4xy-16y
已知(x+2)^2+|x+y+5|=0,求3x^2y-[2x^2y-(2xy-x^2y)-4x^2]-xy
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
已知(4x-2y-1)²+根号(xy-2)=0,求4x³y-4x²y²+xy
已知(4x-y-1)²+根号下x+y-2=0 求4x²y-4xy-xy²
已知xy都是正实数且满足4x²+4xy+y²+2x+y-6=0则x(1-y)的最小值