Hi,
I am running this code
f4=@(x) 0.1*0.4*(0.1*x+100)^(-0.8)-0.1*0.5*(-0.1*x+100)^(-0.8)+0.5*0.1*(0.5*x+100)^(-0.8);
fzero(f4,3)
and it only returns my NaN
Exiting fzero: aborting search for an interval containing a sign change because complex function value encountered during search. (Function value at -230.705 is -0.0043742-0.0033056i.) Check function or try again with a different starting value.
ans =
But if I change that the start poin to 200 I can get the result I want which is 225.3938. My question is how can I get the real root in general case? Before I get the solution I can't tell where is it so I can't choose a proper start point. I can't just randomly try different start points every time when I solve a function like this...
