Re: Solve question

*To*: mathgroup at smc.vnet.net*Subject*: [mg57466] Re: [mg57457] Solve question*From*: Bob Hanlon <hanlonr at cox.net>*Date*: Sun, 29 May 2005 01:03:25 -0400 (EDT)*Reply-to*: hanlonr at cox.net*Sender*: owner-wri-mathgroup at wolfram.com

eqn=a*x^2+b*x+c==0; soln=Solve[eqn,x] {{x -> (-b - Sqrt[b^2 - 4*a*c])/(2*a)}, {x -> (Sqrt[b^2 - 4*a*c] - b)/(2*a)}} The result is a set of rules, {lhs -> rhs}. Rules are used with Replace, ReplaceAll ( /. ), or ReplaceRepeated ( //. ). For example, verifying that the solutions satisfy the original equation: eqn/.soln //Simplify {True,True} Bob Hanlon > > From: "Sterritt, Lanny" <lanny.sterritt at lmco.com> To: mathgroup at smc.vnet.net > Date: 2005/05/28 Sat AM 05:39:41 EDT > Subject: [mg57466] [mg57457] Solve question > > When the Solve command is used to obtain the value of a variable in an equation, something like {x -> value} is returned. How does one get Mathematica to automatically apply this value to following expressions in a notebook? > > L.W.Sterritt > >