Can I insert an iterating value in legends of a plot ?

The code is as follows ; I want to use the iterating b value in the legends . like b=5, b=8 , b=11 etc.

if true
  % code
for b= 5:3:40
f = @(i,o) cotd(o) - cotd(i) - w/c;
fimplicit(f,[0 50 0 50])
legend('beta = ' b );
end
end

Answer 1

[the cyclist]

legend(['beta = ',sprintf('%d',b)])