Re : Simplify
- To: mathgroup at smc.vnet.net
- Subject: [mg14866] Re : [mg14780] Simplify
- From: POITEVINEAU Yvon <ypoit at lac2.gulliver.fr>
- Date: Mon, 23 Nov 1998 10:11:47 -0500
- Sender: owner-wri-mathgroup at wolfram.com
Jurgen Tischer wrote :
>Subject: [mg14866] [mg14780] Simplify
>
>Could someone tell me please how to simplify the following formula?
>
>(-7253*2^(1 + 2*n)*5^n - 523*4^n*5^(1 + n) + 17121*20^n +
> 130321*20^n*n^4)/130321
>
>To my surprise when I changed by hand (with two rules) the powers of 2,
>5 and so on to powers of 20, Mathematica changed them back to this
>form.
Try this :
In[1]:= expr=(-7253*2^(1 + 2*n)*5^n - 523*4^n*5^(1 + n) + 17121*20^n +
130321*20^n*n^4)/130321;
expr/20^n // Expand
Out[1]= n^4
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Yvon Poitevineau