设Q(x,y)在xoy平面上有一阶连续偏导数,曲线积分∫L2xydx+Q(x,y)与路径无关,对任意t恒有
∫L2xydx+Q(x,y)dy从点(0,0)到(t,1)的积分等于从点(0,0)到(1,t)的积分,求Q(x,y)