将xy-e^x+e^y=0两边取导得：ydx+xdy-e^xdx+e^ydy=0解得：dy/dx=﹙y--e^x﹚/﹙x-+e^y﹚当x=0时,∴e^y=1,y=0∴dy/dx|x=0=（0-1）/﹙0+1﹚=-1
