Re: Re: Sinh[y]/y as y->0?
- To: mathgroup at smc.vnet.net
- Subject: [mg33514] Re: [mg33488] Re: Sinh[y]/y as y->0?
- From: Andrzej Kozlowski <andrzej at tuins.ac.jp>
- Date: Sun, 24 Mar 2002 01:44:36 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
Rather than using Limit, which is not very reliable, I would recommend power series expansions. E.g. In[5]:= Normal[(Sin[x]/x) + (Sinh[y]/y)+O[x]+O[y]] Out[5]= 2 etc. Andrzej Kozlowski Toyama International University JAPAN http://platon.c.u-tokyo.ac.jp/andrzej/ On Friday, March 22, 2002, at 09:08 AM, Chris Becker wrote: > You have to use Limit when you want to take a limit, Mathematica won't > immidiatly do this for you. > > Limit[(Sinh[y]/y), y -> 0] > > "aes" <siegman at stanford.edu> wrote in message > news:a7csli$i0t$1 at smc.vnet.net... >> A particular calculation produces at an early stage the intermediate > result >> >> p1 = (Sin[x]/x) + (Sinh[y]/y) , (x and y both real) >> >> and this result then feeds into further expressions in a lengthy >> symbolic >> calculation. >> >> When I try to do any numerical evaluations of the final expressions >> with > either >> x or y = 0, I get "Indeterminate expression" or "infinity 1/0" error > messages, >> even though the expressions themselves, like the expression above, are > perfectly >> determinate and finite for those limits. >> >> Any simple way to make this expression behave as it should under >> numerical >> evaluation? >> > > > > >