Re: Solving multiple equations
- To: mathgroup at smc.vnet.net
- Subject: [mg125555] Re: Solving multiple equations
- From: Peter Pein <petsie at dordos.net>
- Date: Sun, 18 Mar 2012 02:47:23 -0500 (EST)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- References: <jk1g20$51v$1@smc.vnet.net>
Am 17.03.2012 08:55, schrieb Themis Matsoukas:
> I have two set of equations, one in the form,
>
> eq1 = ({0.15, 0.85, X1} == {X3, X2 + X4, X5})
>
> and the other in the form
>
> eq2={1. X1 == 9/5, X4/(X3 + X4 + X5)==1/3}
>
> Solve understands both Solve[eq1] and Solve[eq2] but if I want to solve the two sets simultaneously, what is the best way to combine eq1 and eq2 into a single list of equations, either of the form of eq1 or of eq2, that Solve can understand?
>
> Themis
>
Hi Themis,
to avoid the mixture of exact/inexact numbers and the equations with
scalars/lists, try:
eq1 = {0.15, 0.85, X1} == {X3, X2 + X4, X5};
eq2 = {1.*X1 == 9/5, X4/(X3 + X4 + X5) == 1/3};
Solve[Rationalize @ Join[Thread[eq1], eq2]]]
Peter