Thanks... however something seems strange... it looks like maxima is
trying to simplify the expression and in the end I get
3 - gamma
3/8 - --------- 3 3
1/4 8 2 G M + m G 1/4
4 6 sqrt(7) a sqrt(2 e + 1) sqrt(M) (-----------)
c
a = -----------------------------------------------------------------------]
gamma - 3
5/4 4 2 1/4 Rinfl M 1/8 1/8
5 c (37 e + 292 e + 96) (----------------) (G M)
m
(I hope that the alignment is right)
As you can see, there's an "a" in the right hand side... that's strange
I did this:
(%i1) Fe : 1 + (73/24)*e^2 + (37/96)*e^4$
(%i2) Na : (M/m) * (a/Rinfl)^(3-gamma)$
(%i3) TGW : (5/64) * (c^5/G^3) * a^4/(m*M * (m + M)) * Fe$
(%i4) TRRV : a^(3/2)/(sqrt(G*M)) * M/m * (0.28*(e^2+0.5))^2/sqrt(Na)$
(%i5) solve(TGW=TRRV,a);
Any idea of what might have gone wrong?
thanks
On 12 March 2012 00:56, Leo Butler <l_butler at users.sourceforge.net> wrote:
> Pau <vim.unix at googlemail.com> writes:
>
>> Hi,
>>
>> I am sorry for a rather trivial question... If I have two equations like
>>
>> T(a,e) = a^4 ( 1 - e^3)
>> H(a,e) = e^3 * constants * a^(-1)
>>
>> and I want to find the values of a ,e that equate them
>>
>> T(a,e) = H(a,e) ?---> a = XXXX f(e)
>
> Try
> ? solve
> at the Maxima command line.
>
> A couple notes:
> -the assignment operator in Maxima is :
> -the function definition operator is :=
> -to solve your problem,
> ?I did
>
> (%i1) T : a^4*(1 - e^3) $ H : c*e^3/a $ display2d : false $
>
> (%i4) solve(T=H,e);
>
> (%o4) [e = (sqrt(3)*%i-1)*a^(5/3)/(2*(c+a^5)^(1/3)),
> ? ? ? e = -(sqrt(3)*%i+1)*a^(5/3)/(2*(c+a^5)^(1/3)),
> ? ? ? e = a^(5/3)/(c+a^5)^(1/3)]
>
>>
>> how could I do this in maxima? The best would be an example.
>>
>> Thanks for this nice piece of software. I am looking forward to
>> learning how to use it in detail. Looks very promising.
>>
>> Cheers,
>>
>> Pau
>> _______________________________________________
>> Maxima mailing list
>> Maxima at math.utexas.edu
>> http://www.math.utexas.edu/mailman/listinfo/maxima
>>
>
> --
> Leo Butler ? ? ? ? ? ? ? ?<l_butler at users.sourceforge.net>
> SDF Public Access UNIX System - ? http://sdf.lonestar.org