
Maxima could not solve:
solve: dependent equations eliminated: (6)
(eq9)	[[va=%r1,vb=%r1,vc=%r1,vd=%r1,ve=%r1,vf=%r1,vg=%r1,vh=%r1]]

eq1:(va-ve)/Rae+(va-vd)/Rad+(va-vb)/Rab;
eq2:(vb-va)/Rab+(vb-vf)/Rbf+(vb-vc)/Rbc;
eq3:(vc-vb)/Rbc+(vc-vg)/Rcg+(vc-vd)/Rcd;
eq4:(vd-va)/Rad+(vd-vh)/Rdh+(vd-vc)/Rcd;
eq5:(ve-vf)/Ref+(ve-va)/Rae+(ve-vh)/Reh;
eq6:(vf-ve)/Ref+(vf-vg)/Rfg+(vf-vb)/Rbf;
eq7:(vg-vf)/Rfg+(vg-vh)/Rgh+(vg-vc)/Rcg;
eq8:(vh-vd)/Rdh+(vh-ve)/Reh+(vh-vg)/Rgh;
eq9:solve([eq1,eq2,eq3,eq4,eq5,eq6,eq7,eq8],[va,vb,vc,vd,ve,vf,vg,vh]);

Has swapped R subscripts:
Maxima could not solve:
solve: dependent equations eliminated: (6)
(eq9)	[[va=%r2,vb=%r2,vc=%r2,vd=%r2,ve=%r2,vf=%r2,vg=%r2,vh=%r2]]

eq1:(va-ve)/Rae+(va-vd)/Rad+(va-vb)/Rab;
eq2:(vb-va)/Rba+(vb-vf)/Rfb+(vb-vc)/Rbc;
eq3:(vc-vb)/Rcb+(vc-vg)/Rgv+(vc-vd)/Rcd;
eq4:(vd-va)/Rda+(vd-vh)/Rdh+(vd-vc)/Rdc;
eq5:(ve-vf)/Ref+(ve-va)/Rea+(ve-vh)/Reh;
eq6:(vf-ve)/Rfe+(vf-vg)/Rfg+(vf-vb)/Rfb;
eq7:(vg-vf)/Rgf+(vg-vh)/Rgh+(vg-vc)/Rgc;
eq8:(vh-vd)/Rhd+(vh-ve)/Rhe+(vh-vg)/Rhg;
eq9:solve([eq1,eq2,eq3,eq4,eq5,eq6,eq7,eq8],[va,vb,vc,vd,ve,vf,vg,vh]);

Maxima could not solve:
solve: dependent equations eliminated: (6)
(eq9)	[[vb=va,vc=va,vd=va,ve=va,vf=va,vg=va,vh=va]]

eq1:(va-ve)/Rae+(va-vd)/Rad+(va-vb)/Rab;
eq2:(vb-va)/Rab+(vb-vf)/Rbf+(vb-vc)/Rbc;
eq3:(vc-vb)/Rbc+(vc-vg)/Rcg+(vc-vd)/Rcd;
eq4:(vd-va)/Rad+(vd-vh)/Rdh+(vd-vc)/Rcd;
eq5:(ve-vf)/Ref+(ve-va)/Rae+(ve-vh)/Reh;
eq6:(vf-ve)/Ref+(vf-vg)/Rfg+(vf-vb)/Rbf;
eq7:(vg-vf)/Rfg+(vg-vh)/Rgh+(vg-vc)/Rcg;
eq8:(vh-vd)/Rdh+(vh-ve)/Reh+(vh-vg)/Rgh;
linsolve_params:false$
eq9:solve([eq1,eq2,eq3,eq4,eq5,eq6,eq7,eq8],[va,vb,vc,vd,ve,vf,vg,vh]);

Remove eq1 (va) & eq8 (vh) from solve.
Set va = 1Vdc, Set vh = 0Vdc.
Takes a long time to solve.

eq1:(1-ve)/Rae+(1-vd)/Rad+(1-vb)/Rab;
eq2:(vb-1)/Rab+(vb-vf)/Rbf+(vb-vc)/Rbc;
eq3:(vc-vb)/Rbc+(vc-vg)/Rcg+(vc-vd)/Rcd;
eq4:(vd-1)/Rad+(vd)/Rdh+(vd-vc)/Rcd;
eq5:(ve-vf)/Ref+(ve-1)/Rae+(ve)/Reh;
eq6:(vf-ve)/Ref+(vf-vg)/Rfg+(vf-vb)/Rbf;
eq7:(vg-vf)/Rfg+(vg)/Rgh+(vg-vc)/Rcg;
eq8:(-vd)/Rdh+(-ve)/Reh+(-vg)/Rgh;
eq9:solve([eq2,eq3,eq4,eq5,eq6,eq7],[vb,vc,vd,ve,vf,vg]);


Remove eq1 (va) & eq8 (vh) from solve.
Set R's to 1 Ohm.
Req = 3/4R
Good

eq1:(1-ve)+(1-vd)+(1-vb);
eq2:(vb-1)+(vb-vf)+(vb-vc);
eq3:(vc-vb)+(vc-vg)+(vc-vd);
eq4:(vd-1)+(vd)+(vd-vc);
eq5:(ve-vf)+(ve-1)+(ve);
eq6:(vf-ve)+(vf-vg)+(vf-vb);
eq7:(vg-vf)+(vg)+(vg-vc);
eq8:(-vd)+(-ve)+(-vg);
eq9:solve([eq2,eq3,eq4,eq5,eq6,eq7],[vb,vc,vd,ve,vf,vg]);
eq10:Iae = 1-1/2;
eq11:Iad = 1-1/2;
eq12:Iab = 1-2/3;
eq13:Iin = Iae + Iad +Iab;
eq14:eq13,eq10,eq11,eq12;
eq15:Req = 1/Iin;
eq16:eq15,eq14;


Remove eq1 (va) & eq2 (vh) from solve.
Set va = 1Vdc, Set vh = 0Vdc.
Takes a long time to solve.

eq1:(1-ve)/Rae+(1-vd)/Rad+(1-vb)/Rab;
eq2:(vb-1)/Rab+(vb-vf)/Rbf+(vb-vc)/Rbc;
eq3:(vc-vb)/Rbc+(vc-vg)/Rcg+(vc-vd)/Rcd;
eq4:(vd-1)/Rad+(vd)/Rdh+(vd-vc)/Rcd;
eq5:(ve-vf)/Ref+(ve-1)/Rae+(ve)/Reh;
eq6:(vf-ve)/Ref+(vf-vg)/Rfg+(vf-vb)/Rbf;
eq7:(vg-vf)/Rfg+(vg)/Rgh+(vg-vc)/Rcg;
eq8:(-vd)/Rdh+(-ve)/Reh+(-vg)/Rgh;
eq9:solve([eq3,eq4,eq5,eq6,eq7,eq8],[vb,vc,vd,ve,vf,vg]);

Remove eq1 (va) & eq2 (vh) from solve.
Set va = 1Vdc, Set vh = 0Vdc.
Set all R's to 1.
Still Get Req = 3R/4

eq1:(1-ve)+(1-vd)+(1-vb);
eq2:(vb-1)+(vb-vf)+(vb-vc);
eq3:(vc-vb)+(vc-vg)+(vc-vd);
eq4:(vd-1)+(vd)+(vd-vc);
eq5:(ve-vf)+(ve-1)+(ve);
eq6:(vf-ve)+(vf-vg)+(vf-vb);
eq7:(vg-vf)+(vg)+(vg-vc);
eq8:(-vd)+(-ve)+(-vg);
eq9:solve([eq3,eq4,eq5,eq6,eq7,eq8],[vb,vc,vd,ve,vf,vg]);
eq10:Iae = 1-1/2;
eq11:Iad = 1-1/2;
eq12:Iab = 1-2/3;
eq13:Iin = Iae + Iad +Iab;
eq14:eq13,eq10,eq11,eq12;
eq15:Req = 1/Iin;
eq16:eq15,eq14;


This solves Rah.
Remove eq1 (va) & eq8 (vh) from solve.
Set va = 1Vdc, Set vh = 0Vdc.
Got Req = 3R/4.
This is correct.

eq1:(va-ve)/R+(va-vd)/R+(va-vb)/R;
eq2:(vb-va)/R+(vb-vf)/R+(vb-vc)/R;
eq3:(vc-vb)/R+(vc-vg)/R+(vc-vd)/R;
eq4:(vd-va)/R+(vd-vh)/R+(vd-vc)/R;
eq5:(ve-vf)/R+(ve-va)/R+(ve-vh)/R;
eq6:(vf-ve)/R+(vf-vg)/R+(vf-vb)/R;
eq7:(vg-vf)/R+(vg-vh)/R+(vg-vc)/R;
eq8:(vh-vd)/R+(vh-ve)/R+(vh-vg)/R;
eq9:solve([eq2,eq3,eq4,eq5,eq6,eq7],[vb,vc,vd,ve,vf,vg]),va=1,vh=0;
eq10:eq9[1];
vb:eq10[1];
vd:eq10[3];
ve:eq10[4];
va:1;
Iae:(va-ve)/R,ve;
Iad:(va-vd)/R,vd;
Iab:(va-vb)/R,vb;
Iin:Iae + Iad + Iab;
Req:1/Iin;

This solves Rab
Got R/4 which is wrong

eq2:(vb-va)/R+(vb-vf)/R+(vb-vc)/R;
eq3:(vc-vb)/R+(vc-vg)/R+(vc-vd)/R;
eq4:(vd-va)/R+(vd-vh)/R+(vd-vc)/R;
eq5:(ve-vf)/R+(ve-va)/R+(ve-vh)/R;
eq6:(vf-ve)/R+(vf-vg)/R+(vf-vb)/R;
eq7:(vg-vf)/R+(vg-vh)/R+(vg-vc)/R;
eq9:solve([eq2,eq3,eq4,eq5,eq6,eq7],[vc,vd,ve,vf,vg,vh]),va=1,vb=0;
eq10:eq9[1];
vb:0;
vd:eq10[2];
ve:eq10[3];
va:1;
Iae:(va-ve)/R,ve;
Iad:(va-vd)/R,vd;
Iab:(va-vb)/R;
Iin:Iae + Iad + Iab;
Req:1/Iin;

This solves Rab.
Remove eq1 (va) & eq2 (vb) from solve.
Set va = 1Vdc, Set vb = 0Vdc.
Got Req = 7R/12.
This is correct.

eq1:(va-ve)/R+(va-vd)/R+(va-vb)/R;
eq2:(vb-va)/R+(vb-vf)/R+(vb-vc)/R;
eq3:(vc-vb)/R+(vc-vg)/R+(vc-vd)/R;
eq4:(vd-va)/R+(vd-vh)/R+(vd-vc)/R;
eq5:(ve-vf)/R+(ve-va)/R+(ve-vh)/R;
eq6:(vf-ve)/R+(vf-vg)/R+(vf-vb)/R;
eq7:(vg-vf)/R+(vg-vh)/R+(vg-vc)/R;
eq8:(vh-vd)/R+(vh-ve)/R+(vh-vg)/R;
eq9:solve([eq3,eq4,eq5,eq6,eq7,eq8],[vc,vd,ve,vf,vg,vh]),va=1,vb=0;
eq10:eq9[1];
vb:0;
vd:eq10[2];
ve:eq10[3];
va:1;
Iae:(va-ve)/R,ve;
Iad:(va-vd)/R,vd;
Iab:(va-vb)/R;
Iin:Iae + Iad + Iab;
Req:1/Iin;

This solves Rag.
Remove eq1 (va) & eq7 (vg) from solve.
Set va = 1Vdc, Set vg = 0Vdc.
Got Req = 5R/6.
This is correct.

eq1:(va-ve)/R+(va-vd)/R+(va-vb)/R;
eq2:(vb-va)/R+(vb-vf)/R+(vb-vc)/R;
eq3:(vc-vb)/R+(vc-vg)/R+(vc-vd)/R;
eq4:(vd-va)/R+(vd-vh)/R+(vd-vc)/R;
eq5:(ve-vf)/R+(ve-va)/R+(ve-vh)/R;
eq6:(vf-ve)/R+(vf-vg)/R+(vf-vb)/R;
eq7:(vg-vf)/R+(vg-vh)/R+(vg-vc)/R;
eq8:(vh-vd)/R+(vh-ve)/R+(vh-vg)/R;
eq9:solve([eq2,eq3,eq4,eq5,eq6,eq8],[vb,vc,vd,ve,vf,vh]),va=1,vg=0;
eq10:eq9[1];
vb:eq10[1];
vd:eq10[3];
ve:eq10[4];
va:1;
Iae:(va-ve)/R,ve;
Iad:(va-vd)/R,vd;
Iab:(va-vb)/R,vb;
Iin:Iae + Iad + Iab;
Req:1/Iin;

Remove eq1 (va) & eq8 (vh) from solve.
Set va = 1Vdc, Set vh = 0Vdc.
Takes a long time to solve.

eq1:(va-ve)/Rae+(va-vd)/Rad+(va-vb)/Rab;
eq2:(vb-va)/Rab+(vb-vf)/Rbf+(vb-vc)/Rbc;
eq3:(vc-vb)/Rbc+(vc-vg)/Rcg+(vc-vd)/Rcd;
eq4:(vd-va)/Rad+(vd-vh)/Rdh+(vd-vc)/Rcd;
eq5:(ve-vf)/Ref+(ve-va)/Rae+(ve-vh)/Reh;
eq6:(vf-ve)/Ref+(vf-vg)/Rfg+(vf-vb)/Rbf;
eq7:(vg-vf)/Rfg+(vg-vh)/Rgh+(vg-vc)/Rcg;
eq8:(vh-vd)/Rdh+(vh-ve)/Reh+(vh-vg)/Rgh;
eq9:solve([eq2,eq3,eq4,eq5,eq6,eq7],[vb,vc,vd,ve,vf,vg]),va=1,vh=0;