clear
clc

x=-4:1/100:4;
HyperTangent=tanh(x);

plot(x,HyperTangent,x,x), axis([-4 4 -1 1]);
title('The HyperTangent function (Blue) and the tanh()=x approximation (Green)');
xlabel('x');
ylabel('tanh()');
grid on

clear
clc
