X+y=3 xy=1求-5x-5y+3xy的值
已知xy^2=-2,求-xy(x^2y^5-xy^3-y)的值.
已知x^-xy=5,xy-y^=-3,求式子3(x^-xy)-xy+y^的值
已知,xy/x+y=3,求代数式3x-5xy+3y/-x+3xy-y的值
已知xy/x+y=3,求代数式3x-5xy+3y/-x+3xy-y的值.
已知xy=2(x+y),求(5x-xy+5y)/(3xy-x-y)的值
已知x-y=2xy,求代数式3x-5xy-3y/x+xy-y的值
已知xy/x+y=2,求代数式3x-5xy+3y/-x+2xy-y的值
若x+y-5xy=0,求(2x-3xy+2y)/(x+2xy+y)的值
已知x+y=3,xy=1,求代数式5xy+4x+7y+6x-3xy-4xy+3y的值.
已知1/x-1/y=3,求x-2xy-y/5x+3xy-5y的值
已知1/x+1/y=5,求(3x-5xy+3y)/(x+xy+y)的值?
若1/x+1/y=5,求3x+4xy+3y/x+3xy+y的值