$.$Write a Matlab program.

$.$Compute functions with Matlab.

$.$ Plot graph of function

Exercise $3$:

These statements plot three related functions of $x$ :

$y1=2cos(x),$

$y2=cos(x),$

and $y3={0\mathrm{.}5}^{**}cos(x)$

in the interval $0*x*2.$

Plot the graph

Named the axis

Named the graph

Put the MATLAB screenshot here