# Solving non-linear equation including natural logarithm

4 views (last 30 days)
Ogulcan Acikgoz on 20 Nov 2019
Commented: Ogulcan Acikgoz on 21 Nov 2019
Hi guys, I am trying to solve this eqn for y and I am just waiting, Matlab stays busy for some reason. What can I do? Do you think there is a simple way to do it?
syms a b c x y
eqn = (1/b) * (c-y)^(3/2) == a-x-(1/2)*log(1-y/c)
eqn=rewrite(eqn,'log')
s=solve(eqn,y,'IgnoreAnalyticConstraints',true)

Jeremy on 20 Nov 2019
Edited: Jeremy on 20 Nov 2019
Most probably, there is no analytical solution for y in terms of (a,b,c,x). You can solve numerically for y at given values of a,b,c,x by using fzero.
Ogulcan Acikgoz on 21 Nov 2019
It seems a good idea, thank you. I am sure it is very easy but I tried to solve and I could not manage to write the code for regression. Also I tried to use curve fitting toolbox and it gave me an error saying that it is too complex.

R2018b

### Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!