In [1]:

    

import sympy

sa = sympy.symbols('c f b e', real=True)
c, f, b, e = sa

sb = sympy.symbols('a d', real=True, positive=True)
a, d = sb


#a = I0
#b = Ia
#c = Va
#d = n
#e = Ib
#f = Vb


eqnSys1 = -a*(sympy.exp(38.4064846567063*(0.515107067876097*b + c)/d) - 1) - 1.0006522465381*b - 0.00126623488352542*c + 8.68885843001594
eqnSys2 = -a*(sympy.exp(38.4064846567063*(0.515107067876097*e + f)/d) - 1) - 1.0006522465381*e - 0.00126623488352542*f + 8.68885843001594

eqnSys = (eqnSys1,eqnSys2)


    

In [ ]:

    

sympy.solve(eqnSys,(a,d))


    

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