need sugestion to solve exponential series

I am trying to solve following equation with matlab.anyone please give me some suggestion how can i find value of R1....R7 and C1....C7.

Z(t)=∑_(i=1)^n(R_i  (1-e^(-t/(R_i C_i )) )
Z(t)=0.004

And t=10, n=7

Thanks

Answer 1

[Walter Roberson]

n = 7;
R = sym('R', [1 n]);
C = sym('C', [1 n]);

t = 10;
Ztval = 0.004;

Zt = sum( R .* (1 - exp(-t ./( R .* C ) ) ) );
solC1 = solve(Zt == Ztval, C(1), 'ReturnConditions', true);

This will give you solC1.C1 as a solution for C1, subject to a condition listed in solC1.conditions

You cannot solve for all 14 variables when you only have one equation.