Re: symbolic approximation (formular manipulation)
- To: mathgroup at smc.vnet.net
- Subject: [mg55051] Re: symbolic approximation (formular manipulation)
- From: Paul Abbott <paul at physics.uwa.edu.au>
- Date: Thu, 10 Mar 2005 05:25:18 -0500 (EST)
- Organization: The University of Western Australia
- References: <d0mnef$71b$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
In article <d0mnef$71b$1 at smc.vnet.net>, Zhe Hu <iamhuzhe at gmail.com>
wrote:
> A formula in electrical engineering can be simplified after assuming,
> e.g. R1<<R2, within 10% error tolerance.
>
> How this kind of "simplify" or approximation can be performed by Mathematica?
>
> For example, R1<<R2, R2<<R3
>
> R1+R2 R2 R2
> --------------- ---> ------------------ ---------> ------------------
> R1(R2+R3) R1(R2+R3) R1 R3
Use Series.
Normal[Series[(R1 + R2)/(R1 (R2 + R3)), {R1, 0, -1}, {R2, 0, 1}]]
Cheers,
Paul
--
Paul Abbott Phone: +61 8 6488 2734
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