We are trying to find the roots of a function where exp(f(z)) = c. (where c is a complex number). Also f(z) is a polynomial function. The function will have the following format:(adsbygoogle = window.adsbygoogle || []).push({});

expsolve( [an an-1 …] , c ) where n is the degree of “z”.

For do this I took the natural logarithm of both sides and find f(z) = log(c). The code I have written so far is as follows;

function expsolve(v,c);

len=length(v)

temp=log(c);

syms z;

syms def;

syms first;

first=0;

for(a=1:len)

def=v(len-a+1)*(z^(a-1))

first=first+def

end

first

equ=first-log(c)

--------------------

now if I write expsolve([1 5 3], 4) for instance

until the first part it gives me the correct result (first=z^2+5*z+3)

however, I could not do the rest. how can I find the roots of first-log(c).

I tried to write different combination of :

solve('equ=0','z').

However, it gave my either an error or a illogical answer.

How can I proceed in this question. Besides the code I have written is there any simpler way to solve the question?

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# How to use solve function in matlab in this case

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