Solving Transcendental Equations

Dear all,

I am trying to solve the following transcendental equation using 'solve':

[y]=solve((a-((x+b*x)/c)-(p*(exp((x+b*y)/(d))-1))-(q*(exp((x+b*y)/(2*d))-1))),y)

And I get the following result:

=========================== Warning: List of equations is empty. > In solve at 70

i =

[ empty sym ]

================================

What does this really mean? Is there something wrong with the equation?

Any help to solve this would be much appreciated.

Thanks,

Answer 1

[Walter Roberson]

If you happen to have defined values for any of those names, and one of the values is the empty array, then the expression overall would become the empty array, leading to the warning that you see.

[Pratibha]

I am new to Matlab so could you tell me how to fix this. I have defined values for the following constants:

a= 0.014

b=10

c=10000

d=0.026

p=1e-7

q=1e-7

and I would want the solution to this problem in terms of x

How can I do that?

[Pratibha]

In addition when I only evaluate the expression with one exponential term as follows:

syms x y

a= 0.014

b=10

c=10000

d=0.026

p=1e-7

q=1e-7

m= solve((a-((x+b*y)/c)-(p*(exp((x+b*y/(d))-1)))-y),y)

It gives me this result:

m= 2/143 - (13*lambertw(0, (exp(x)*exp(10000/1859 - (500*x)/13013))/(26026*exp(1))))/5000 - x/10010

------

I am wondering why it doesn't work with the second exp term added in.

I would appreciate your help with the same.

Thanks

[Walter Roberson]

syms x y

a= 0.014

b=10

c=10000

d=0.026

p=1e-7

q=1e-7

[y]=solve((a-((x+b*x)/c)-(p*(exp((x+b*y)/(d))-1))-(q*(exp((x+b*y)/(2*d))-1))),y)

[Alexander]

What version are you using? This does give me a result with 2012a.