[moved] Solution of Complex Exponential Equation

[vijender13]

Hi all,
I am trying to find out two unknowns from two equation. The equation are given below

eqn1 = exp((t0-tm)*(k3+k4)) -1 == (exp(-k4*(tr-t0))-1) / (exp(-tr)+exp(-t0));
eqn2 = exp((tr-tm)*(k3+k4)) -1 == (exp(k4*(tr-t0))-1) / (exp(-tr)+exp(-t0));

I want to calculate k3 and k4 in terms of to,tm,tr. I have tried this using 'solve' command in matlab but it gives me a empty matrix.

code:

syms k3(t0,tm,tr) k4(t0,tm,tr)
solve(eqn1 eq2)

Any idea how to get K3 and K4 from these equation.


Thanks

 

[KlausST]

Hi,

I can't solve it.

Did you consider to use Laplace transform?
With this you can get rid of thone exp functions.

Klaus

 

[vijender13]

Hi Klaus,

Thanks for your reply.

I don't understand why Laplace is helpful here. If I do laplace transform then its too complicated.

Vijender

 

[KlausST]

Hi,

As far as I know the laplace transform of an exp will give a "multiply"...
This easier to solve.

But I may be wrong.... it's so many years ago..

Klaus

 

[albbg]

What are the values of t0,tm,tr you want to solve for ?
However "solve" is for system of linear equation. You have non-linear equation, so you have to use "fsolve"