已知x+y=6,xy=7,则x^2+y^2=_____,x^2+xy^2=____

已知x-y=4xy，则2x+3xy-2yx-2xy-y 已知X+y=6,xy=7 求x^2y+xy^2= 已知x+y=6,xy=-3,则x^2y+xy^2=? 已知x+y=6,xy=-3,则x^2y+xy^2= 已知xy/x+y=1/2,则代数式3x-5xy+3y/-x+3xy-y= 已知xy/x+y=6,求3x-2xy+3y/-x+3xy-y的值. 已知:x/y=-2,求x^2-2xy-3y^2/x^-6xy 已知x>0,y>0且3x+2y-2xy=0,则xy的最小值是____ 已知x-xy=8,xy-y=-9,求x+y-2xy的值 已知x^2-y^2=27,x-y=3则xy=____,x^2+y^2=_____ 由已知x+y=-2,xy=3那么2(x+xy)-[(xy-3y)-x]-(-xy)等于多少? 已知1/x=1/y=6,则3x-2xy+3y/3xy+x+y=?