Re: Solve / Reduce isolating results.
- To: mathgroup at smc.vnet.net
- Subject: [mg118499] Re: Solve / Reduce isolating results.
- From: leni536 <leni536 at gmail.com>
- Date: Sat, 30 Apr 2011 05:50:49 -0400 (EDT)
- References: <ipe7p9$r42$1@smc.vnet.net>
On =E1pr. 29, 13:35, "Lea Rebanks" <lreba... at netvigator.com> wrote:
> Dear All,
>
> Given the enclosed code - see below.
> Please could someone help me setup the code to Solve / Reduce for these 2
> missing values only required
>
> {SQ1 -> 5292,
> XX -> 0.25}
>
> (I don't want multiple results.) I want positive numbers & NOT Complex..
>
> Many thanks for your help & attention, really appreciated. Please see below.
>
> Best regards,
> Lea...
> ...................................................................
>
> Clear[SQ1]
> Clear[XX]
> Solve[{(1/6)*((SQ1*196)*2)^3 -
> (1/6)*((((2.75 + XX)*((3.75 + XX)*21^2))*100)*2)^3 ==
> 1.2902698935932682*^18, (1/6)*((SQ1*100)*2)^3 -
> (1/6)*((((2.75 + XX)*((3.75 + XX)*21^2))*36)*2)^3 ==
> 1.883856772422697*^17}, {SQ1, XX}]
Clear[SQ1]
Clear[XX]
positiveRealQ[x_] := If[Im[x] == 0, x > 0, False];
Select[{SQ1, XX} /.
Solve[{(1/6)*((SQ1*196)*2)^3 - (1/
6)*((((2.75 + XX)*((3.75 + XX)*21^2))*100)*2)^3 ==
1.2902698935932682*^18, (1/6)*((SQ1*100)*2)^3 - (1/
6)*((((2.75 + XX)*((3.75 + XX)*21^2))*36)*2)^3 ==
1.883856772422697*^17}, {SQ1, XX}],
And @@ (positiveRealQ /@ #) &
]
Regards,
Lenard