一阶导数你求对了令 t = dy/dx = cos(x+y)/[1-cos(x+y)] dy = cos(x+y)·dx/[1-cos(x+y)] dx+dy = cos(x+y)·dx/[1-cos(x+y)] + dx = dx/[1-cos(x+y)] t+1 = 1+ cos(x+y)/[1-cos(x+y)] = 1/[1-cos(x+y)] 那么原函数...