Unable to find explicit solution

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seema redhu
seema redhu 2021-12-4
评论： Walter Roberson 2022-1-10
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
  4 个评论
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G A
G A 2021-12-6
编辑：G A 2021-12-6
Ran in:
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);

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回答（2 个）

seema redhu
seema redhu 2021-12-6
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);
  1 个评论
Walter Roberson
Walter Roberson 2022-1-10
Maple thinks that 3.33507942113645790766889887448*10^(-304) might be a solution.

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G A
G A 2021-12-6
编辑：G A 2021-12-6
Your equation with actual ratio a4/a3 does not have analytical solution. Try to solve it numerically with some tolerance.

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