%% Plot Hyperbolic Cosine and Exponential Functions
% The hyperbolic cosine satisfies the identity \cosh \left(x\right)=\frac{e^x +e^{-x} }{2}. In other words, \cosh \left(x\right) is the average of e^x and e^{-x}. Verify this by plotting the functions.
%
% Create a vector of values between -3 and 3 with a step of 0.25. Calculate and plot the values of cosh(x), exp(x), and exp(-x). As expected, the curve for cosh(x) lies between the two exponential curves.

x = -3:0.25:3;
y1 = cosh(x);
y2 = exp(x);
y3 = exp(-x);
plot(x,y1,x,y2,x,y3)
grid on
legend('cosh(x)','exp(x)','exp(-x)','Location','bestoutside')

% Copyright 2018 The MathWorks, Inc.