how to find value of variable in natural logarithmic
2 visualizaciones (últimos 30 días)
Mostrar comentarios más antiguos
How to find value of X:
ln(X/0.466)*66.66+X*4.4805*10^(-4)+X=5.66
4 comentarios
Star Strider
el 30 de Abr. de 2021
I would use fsolve, since it would appear to have at most only one root.
Remember to use log, not ln in your code.
Respuestas (1)
DGM
el 30 de Abr. de 2021
Editada: DGM
el 30 de Abr. de 2021
This can be done a number of ways. It's a log plus a positive linear function of x. There will be only one solution. That makes everything easier.
% solving symbolically
syms X
eqn = log(X/0.466)*66.66+X*4.4805*10^(-4)+X==5.66;
aaa = double(solve(eqn,X))
% or using fsolve
f = @(x) log(x/0.466)*66.66 + x*4.4805*10^(-4) + x - 5.66;
bbb = fsolve(f,1)
% or using fzero
ccc = fzero(f,1)
% do the answers make sense? check it graphically
x = linspace(0.2,1,100);
y = log(x/0.466)*66.66 + x*4.4805*10^(-4) + x;
plot(x,y); hold on
plot([0.2 1],[1 1]*5.66)
plot(aaa,5.66,'bo')
plot(bbb,5.66,'ko','markersize',10)
Ver también
Categorías
Más información sobre Calculus en Help Center y File Exchange.
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!