       Re: Rule and First

• To: mathgroup at yoda.physics.unc.edu
• Subject: Re: Rule and First
• From: alex at fff.chem.utah.edu (Alex Dommasch)
• Date: Fri, 10 Jul 92 08:50:28 MDT

```> Hi Mathgroup,  I am trying to pick out the value of l from the following
> 		equation:
>

>

> 	In:= FindRoot[(Exp[28*l]-Exp[l])/((Exp[20*l]-Exp[l])
> 		 *((1+l)^8))== ratio, {l,0.01}]
>

> 	Out= {l -> 0.0395991}
>

>

I'm not sure if this is what you want, but this is how I always go about getting
a value out of a rule:

In:= lrule = FindRoot[(Exp[28*l]-Exp[l])/((Exp[20*l]-Exp[l])
*((1+l)^8)) == 2, {l,0.01}]

Out= {l -> -0.0652571}

In:= l /. lrule

Out= -0.0652571

In:= l2 = l /. lrule

Out= -0.0652571

Hope this helps.
--
Alex Dommasch, Programmer                       |--

Field-Flow Fractionation Research Center        |-

Department of Chemistry, University of Utah     V

Salt Lake City, Utah 84112                      |->|..
(801)581-7168           FAX: (801)581-4353      |- |.

alex at fff.chem.utah.edu (NeXT Mail)              |  |

```

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