<kounoike@mbh.nifty.com> wrote in message news:<c7t8bu$5j9$1@caraway.media.kyoto-u.ac.jp>...
> "Y.N." <yoshiro@mail.wind.ne.jp> wrote in message
> news:c7suhv$fe6$1@nr1.vectant.ne.jp...
> > M> ?f'(x)?lim{?x?0}[{f(x+?x)-f(x)}/?x] ???????? dy??f'(x)
>  ??x
> > M> ?????????dy?f'(x)dx ?????????????????
> >
> > ??????(^^)?
> >
> > ? y?f(x)
> >  ?y?A??x????x ?A ? ?x ??????x?0 ??????0??
> >  ????????
> >   f'(x):?A?dy:?f'(x)?x?
> >
> > ????????????????(^0^)?
> 
> ?????????????????????????
> ??????????????????
> ?y?A??x????x ????????
> ???f''(x)?????????????



  Y.N.????????????Cauchy ????? f'(x) ? 
lim{?x?0}?{f(x??x}?f(x)}??x????????
f''(x) ? lim{?x?0}?{f'(x??x}?f'(x)}??x?????
??????????(differential) dy?????? d^2y ?
?????????(limit)????????????????
??????? 

????????dy ? dy??f'(x)??x ?????????
????dy?f'(x)dx ????????????????????
d^2y?f''(x)(dx)^2 ?????????????????
*??????*?????N_Bourbaki ???????????
?????????????

??????dy??f'(x)??x ??*??? --- ??????
? --- ??* ????????????????????