Unable to find explicit solution

syms y b a x c d f
eqn = b+(a*log(y/x))==c+(d*log((1-y)/f));
soly = solve(eqn, y)

Warning: Unable to find explicit solution. For options, see help.

> In solve (line 317)

In Plotting (line 30)

soly =

Empty sym: 0-by-1

What is wron with my code

[G A]

you have equation of type

y/(1-y)^A=B

which does not have an explicit solution for any A, but you can try with integer A

[seema redhu]

Please rewrite tha same code with integer A

[G A]

is it OK as follows?

syms y a b c d f x A B 
n=2;
d = n*a

d = 

A = d/a

A = 

2

y = solve(y/(1-y)^A==B,y)

y = 

B = (x/f^A)*exp((c - b)/a);

[Walter Roberson]

http://www.mathworks.co.uk/matlabcentral/answers/43073-a-guide-to-tags

Answer 1

[seema redhu]

Hi Sir

My actual code with parameters are as below-

I have to solve this for the value of y.Please help me to solve this.

syms y a1 a2 a3 a4 a5 a6 
a1=-2.9362;
a2=-133.2985;
a3=0.1864;
a4=0.1717;
a5=0.95;
a6=0.5;
p=a1+(a3*log(y/a5));
q=a2+(a4*log((1-y)/a6));
r=p==q;
h=solve(r,x);

[Walter Roberson]

Maple thinks that 3.33507942113645790766889887448*10^(-304) might be a solution.

Answer 2

[G A]

Your equation with actual ratio a4/a3 does not have analytical solution. Try to solve it numerically with some tolerance.