X+Y=50 XY=616 求XY
如果xy+x+y=6,试求自然数 xy
已知x-xy=8,xy-y=-9,求x+y-2xy的值
已知x^2-xy=5,xy-y^2=-3求3(x^2-xy)-xy+y^2
已知x+y=12,xy=9,求(x+3xy+y)/(xy+xy)的值
已知x^-xy=5,xy-y^=-3,求式子3(x^-xy)-xy+y^的值
已知xy^2=-2,求-xy(x^2y^5-xy^3-y)的值.
已知xy^2=-2 求-xy(x^2y^5-xy^3-y)
已知x:y=3:2,求(x²+3xy)/(xy+2xy)
y'+xy=x^3求微分
已知xy为正整数,3xy=2x+3y+5.求xy=?
已知XY为正数,X+Y=1 求1/XY+XY的最小值
设xy>0,且xy=4x+y+12,求xy的最小值