Tau Membership Function

alpha=30;
beta = 40;
for i=1:10
  x(i) = i*5
  if x(i)<=alpha
    y(i)=0;
  elseif x(i)<=beta
    y(i) = (x(i)-alpha)/(beta-alpha)
  else
     y(i)=1
  end
end
plot(x,y)