Re: Expand for the TI-85

Subject: Re: Expand for the TI-85
From: C Kuethe <ckuethe@GPU.SRV.UALBERTA.CA>
Date: Thu, 24 Oct 1996 17:46:51 -0600
In-Reply-To: <9610242321.AA23389@aztec.asu.edu>

On Thu, 24 Oct 1996, MICHAEL J. COCCARO wrote:


> The TI-92 can expand a binomial like (a+b)^4 using the expand program.
>


Use nCr...


(x*a^n+...+b*y^n)   (n+1) (e[i])
-----------------   ----- ------
      1               1 nCr 1
     1 1              2 nCr 1  , 2 nCr 2
    1 2 1             3 nCr 1  , 3 nCr 2  , 3 nCr 3
   1 3 3 1            4 nCr 1  , 4 nCr 2  , 4 nCr 3  , 4 nCr4
  1 4 6 4 1
1 5 10 10 5 1


and so on.  The point of this is that this gives you the coefficients...


(a+b)^3 [n=3] ==> (1 a^3 b^0)+(3 a^2 b^1)+(3 a^1 b^2)+(1 a^0 b^3)


look at row n+1 (4)
see the coeff's (1,3,3,1)
look at the expansion (a+b)^3
see the coeff's (1,3,3,1)


input "row #:",n
n->DimL R
for(x,1,n+1)
(n+1) nCr x -> R(x)
end
Pause R


it's not pretty but it works...
<pre>
--
Chris Kuethe <ckuethe@gpu.srv.ualberta.ca> LPGV Electronics and Controls


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$/=unpack('H*',$_);$_=`echo 16dio\U$k"SK$/SM$n\EsN0p[lN*1
lK[d2%Sa2/d0$^Ixp"|dc`;s/\W//g;$_=pack('H*',/((..)*)$/)
</pre>

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