Cannot solve x*tan(x/w)=C in matlab, please help

The equation is x*tan(x/w)=C and .

w = 1e-6 C = 3.5e3

Here's how I do it:

x0 = pi/4

eq = sprintf('x*tan(x/%g) == %g', w, C);

gamma_pde = fzero(eq4, x0)

Depending on the value of x0, I get different results which are totally wrong, and do not work in the original equation. I know that this equation has infinite number of answers, that's why I'm setting x0, but I dont seem to have any luck solving it with matlab.

I dont know if I can use some other commands like solve, b/c this equation has so many answer.

Thanks for reading.

[Oleg Komarov]

Please format the code properly: http://www.mathworks.com/matlabcentral/answers/7885-tutorial-how-to-format-your-question

Answer 1

[Oleg Komarov]

eq4 = @(x) x*tan(x/w)-C;

Use anonymous functions but be careful with the constants (see paragraph Variables Used in the Expression)