Re: Solve / Reduce isolating results.
- To: mathgroup at smc.vnet.net
- Subject: [mg118616] Re: Solve / Reduce isolating results.
- From: Dana DeLouis <dana.del at gmail.com>
- Date: Wed, 4 May 2011 06:36:12 -0400 (EDT)
> {SQ1 -> 5292, XX -> 0.25} > ... I want positive numbers & NOT Complex.. Hi. Just to be different... I just added XX > 0 to your original equations: equ={(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, XX>0} //Rationalize[#,0]& //Simplify { 30118144/3 (-128520857088+SQ1^3-11390625 (11/4+XX)^3 (15/4+XX)^3)==0, (4000000 SQ1^3)/3==197605142784 (953344+27 (11/4+XX)^3 (15/4+XX)^3), XX>0 } t=Solve[equ,{SQ1,XX},Reals] {{SQ1->5292,XX->1/4}} = = = = = = = = = = HTH : >) Dana DeLouis = = = = = = = = = = On Apr 29, 7:35 am, "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}]