Re: significance arithmetic and numeric equation solving

• To: mathgroup at smc.vnet.net
• Subject: [mg61589] Re: [mg61576] significance arithmetic and numeric equation solving
• From: Pratik Desai <pdesai1 at umbc.edu>
• Date: Sun, 23 Oct 2005 05:45:52 -0400 (EDT)
• References: <200510220911.FAA15007@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

```Chris Chiasson wrote:

>Hello MathGroup,
>My last confession was...
>er...
>NSolve seems able to carry through significance arithmetic. FindRoot
>and NDSolve seem inable to do so.
>I would like to be able to solve the following equation for acCap[0]
>assuming cNapRatio->0
>(sorry about the FullForm, but I had to rid the post of the one way
>Notations I made), does anyone know a way to get Mathematica to do
>this?
>
>Equal[Times[Power[Log[10],-1],Log[acCap[cNapRatio]]],
>  Plus[Times[0.6107999999999999999`0.9956786262173576,cNapRatio],
>    Times[-2.0360000000000000001`2.9999999999999996,
>      Plus[Times[-0.0061540230743798795`0.9978339382434933,
>          Power[acCap[cNapRatio],-2],
>          Power[Power[acCap[cNapRatio],2],Rational[1,2]]],
>        Times[Power[2,Rational[-1,2]],
>          Power[Plus[Times[2,cNapRatio],
>              Times[0.0410268204958658633`3.3010299956639817,
>                Power[acCap[cNapRatio],-2],
>                Power[Power[acCap[cNapRatio],2],Rational[1,2]]]],
>            Rational[1,2]],
>          Power[Plus[1,
>              Times[Power[2,Rational[-1,2]],
>                Power[Plus[Times[2,cNapRatio],
>                    Times[0.0410268204958658633`3.3010299956639817,
>                      Power[acCap[cNapRatio],-2],
>                      Power[Power[acCap[cNapRatio],2],Rational[1,2]]]],
>                  Rational[1,2]]]],-1]]]]]]
>
>--
>Chris Chiasson
>http://chrischiasson.com/contact/chris_chiasson
>
>
>
Hey Chris

Here is my somewhat belabored attempt, hope this is what you are looking
for

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RowBox[{
RowBox[{"Power", "[",
RowBox[{
RowBox[{"Log", "[", "10", "]"}], ",",
RowBox[{"-", "1"}]}], "]"}], ",",
RowBox[{"Log", "[",
RowBox[{"acCap", "[", "cNapRatio", "]"}], "]"}]}],
"]"}], ",",
RowBox[{"Plus", "[",
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RowBox[{"Times", "[",
RowBox[{"0.6107999999999999999`0.9956786262173576", ",",
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RowBox[{"-", "2"}]}], "]"}], ",",
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RowBox[{
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RowBox[{"Rational", "[",
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RowBox[{"0.0410268204958658633`3.3010299956639817", ",",
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RowBox[{"Plot", "[",
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RowBox[{"acCap", "[", "0", "]"}]}], "Input"]

Hope this helps

Pratik  .

--
Pratik Desai