MATLAB: Non linear equation solution problem

equationnonlinearsolvesymbolic

clear all
clc
syms x xe k n CR T
Tin=915;
CR=1;
xe=1;
eq=(xe*k^n*((Tin-T)/CR)^n)/(1+k^n*((Tin-T)/CR)^n)==x;
eq1=subs(eq,T,888);
eq1=subs(eq1,x,5.43/100);
eq2=subs(eq,T,840);
eq2=subs(eq2,x,73/100);
sol=solve([eq1,eq2],[k,n]);

Best Answer

The equation is too complicated for MATLAB.
The solutions are:
ln = @log;
k = exp(-(ln(73/(100*xe-73))*ln(25/9)+ln(75)*ln(543/73*(100*xe-73)/(10000*xe-543)))/ln(543/73*(100*xe-73)/(10000*xe-543)))
n = -ln(543/73*(100*xe-73)/(10000*xe-543))/ln(25/9)
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