xfxygy()d()d.xfxygy()d)d((C).y=y(x,C)..:211yx,1ddx2xyarctanyxC()x24xy,,1C,(4,2)arctan+1.yx1.(4,2)2.xydxdy2xdxydy2xdxydy212|ln|Cxy2112xCCxeeeyeC1,C.Cex2y:(C.)()()[()],0dhtkhtHhtkdt常数11[lnln()],hHhktCH.,()dhkdthHh(),1kHtHhtCe+lim().thtHHth(t)C1.C>0.h(t):LogisticSOht()1kHtHhte.L...