Re: 2 stage solution with FindRoot

*To*: mathgroup at smc.vnet.net*Subject*: [mg57449] Re: 2 stage solution with FindRoot*From*: "Mukhtar Bekkali" <mbekkali at gmail.com>*Date*: Sat, 28 May 2005 05:39:15 -0400 (EDT)*References*: <d76och$7pd$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Correction by example: I have functions f1[x1,x2,y1,y2] and f2[x1,x2,y1,y2]. I need to solve the problem the following way. First, I need to solve for {x1,x2}={{x1,x2}|D[f1,x1]=0&&D[f2,x2]=0}. A solution is {x1[y1,y2],x2[y1,y2]}. Substituting into original functions yields f1[x1[y1,y2],x2[y1,y2],y1,y2] and f2[x1[y1,y2],x2[y1,y2],y1,y2]. Then, I need to solve for {y1,y2}={{y1,y2}|D[f1[x1[y1,y2],x2[y1,y2],y1,y2],y1]=0&&D[f2[x1[y1,y2],x2[y1,y2],y1,y2],y2]=0} I apoligize for misspecification of the problem.