Re: Setting up equations
- To: mathgroup at smc.vnet.net
- Subject: [mg66027] Re: Setting up equations
- From: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
- Date: Thu, 27 Apr 2006 02:26:26 -0400 (EDT)
- Organization: The Open University, Milton Keynes, UK
- References: <e2nd3i$33m$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Yaroslav Bulatov wrote:
> I'm trying to do things of the form
> Solve[5 x + 6 y + 7 z == a x + b y + c z, {a, b, c}]
>
> But since x,y,z are variables, what I really mean is
> Solve[5==a && 6==b && 7==c], so I need to convert to this form
>
> If I only have one variable, the following does what I need
>
> LogicalExpand[a*x + b*x^2 + O[x]^3 == 2*x + 3*x^2 + O[x]^3]
>
> But what to do if I have several variables?
>
Hi Yaroslav,
Try *Reduce* rather than *Solve* and use *ForAll* to put a condition on
x, y, and z.
In[1]:=
Reduce[ForAll[{x, y, z}, 5*x + 6*y + 7*z ==
a*x + b*y + c*z], {a, b, c}]
Out[1]=
a == 5 && b == 6 && c == 7
Best regards,
Jean-Marc