Re: HELP!
- To: mathgroup at smc.vnet.net
- Subject: [mg81192] Re: HELP!
- From: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
- Date: Sat, 15 Sep 2007 04:09:44 -0400 (EDT)
- Organization: The Open University, Milton Keynes, UK
- References: <fcdfdj$pnr$1@smc.vnet.net>
conoverm at vt.edu wrote:
> How do i put a code in Mathematica 6.0 lab worksheet 2 of calculus I where I
> need to use sigma notation of (1/n!)
> I tried doing it but when i make a table it does not add the products of 1-3 if
> i put in as n goes to 3. Please help me with the code. Thank You
>
> \[ExponentialE]=\!\(
> \*UnderoverscriptBox[\(\[Sum]\), \(n = 0\), \(\[Infinity]\)]
> \*FractionBox[\(1\), \(n!\)]\)=1+1/1!+1/2!+1/3!+1/4!+...
I am pretty sure I have not correctly understood what the problem is
(i.e. typesetting or evaluating the sum expressed in sigma notation),
but here are some examples that, I hope, will help your anyway. (They
illustrate some of the feature of function such as Table, HoldForm, N, etc.)
In[1]:= Sum[1/n!, {n, 0, 3}]
Out[1]=
8
-
3
In[2]:= Plus @@ FoldList[1/HoldForm[#2]! &, 1, Range[5]]
Out[2]=
1 1 1 1 1
1 + -- + -- + -- + -- + --
1! 2! 3! 4! 5!
In[3]:= HoldForm@Sum[1/n!, {n, 0, 5}] ==
Plus @@ FoldList[1/HoldForm[#2]! &, 1, Range[5]]
Out[3]=
1 1 1 1 1 1
Sum[--, {n, 0, 5}] == 1 + -- + -- + -- + -- + --
n! 1! 2! 3! 4! 5!
In[4]:= Limit[Sum[1/n!, {n, 0, x}], x -> Infinity]
Out[4]= E
In[5]:= Table[N@Sum[1/n!, {n, 0, x}], {x, 1, 5}]
Out[5]= {2., 2.5, 2.66667, 2.70833, 2.71667}
HTH,
--
Jean-Marc