%fnc - funkcja
%dfnc - pochodna funkcji
function [z, iters] = newton(x0, epsilon, max_iter,fnc, dfnc)
x = x0;
x1 = x0 - eval(fnc)/eval(dfnc);
z = [x1];
i = 0;
while abs(x0 - x1) > epsilon && i < max_iter,
    i = i + 1;
    x0 = x1;
    x=x0;
    x1 = x0 - eval(fnc)/eval(dfnc);
    z = [z; x1];
end
iters = i;