帮个忙啦 已知x+y=-6 xy=8 求√y/x+√x/y
帮个忙啦 已知x+y=-6 xy=8 求√y/x+√x/y
已知x的平方+y的平方-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
已知x²+y²-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
已知y=√(x-8)+√(8-x)+18,求代数式 (x+y)/(√x-√y)-2xy/(x√x-y√x) 的值
已知xy=-2,x-y=3,求(x+y)(x-y)-y^2+(x-y)^2-(6x^2y-2xy^2)÷2y
已知|x²-2xy-8y²|+2√x²-4xy+4y²-1=0,求3x+6y的值
已知x.x+y.y+8x+6y+25=0,求代数式(x.x-4y.y)/(x.x+4xy+4y.y)-x/(x+2y)的
已知x+y=3,xy=6,.求根号x/y+根号y/x
已知xy=-2,x-y=3,求(x+y)(x-y)-y²+(x-y)²-(6x²y-2xy
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
√x(√x+2√y)=√y(6√x+5√y,求x-3√xy+2y/x+√xy-6y
已知:x/y=-2,求x^2-2xy-3y^2/x^-6xy