u'x-v'x=2x u'y-v'y=-2y 因为解析,u'x=v'y,u'y=-v'x u'x=x+y=v'y u'y=x-y=-v'x u=0.5x^2+xy-0.5y^2 v=0.5y^2+xy-0.5x^2
