已知x+y=4,xy=2,则x2+y2+3xy=______.
已知x+y=4,xy=2,则x2+y2+3xy=______.
已知xy=-3,x+y=-4,则x2+3xy+y2值为______.
已知x+y=4,xy=2,求x2+y2+3xy的值.
已知x2+xy=3,xy+y2=-2,则2x2-xy-3y2=______.
已知x+y=5,xy=3 则x2+y2=______.
已知实数x,y满足x2+xy+y2=3,则x2-xy+y2的最小值
已知xy=3,x2+xy-2y2=2(x+2y),且x≠-2y,则x+y=______.
已知2x-3*根号(xy)-2y=0(x>0),则x2+4xy-16y2除以2x2+xy-9y2的值是多少?
已知x、y是实数且满足x2+xy+y2-2=0,设M=x2-xy+y2,则M的取值范围是______.
已知2x=3y,求xy/(x2+y2)-y2/(x2-y2)的值
已知x+y=3,x2+y2-3xy=4,则x3y+xy3的值为______.
已知x+y=17,xy=60,则x2+y2=______.