Here is the gist, but with a different function. I can see that this problem is worth 2 points, so I won't do your homework for you. This will be close enough for you to get the basics of plotting and then apply it to your own problem.
x = 0:0.1:100; %make x values to put into the function
y = sin(x)+5+1e-3*x.^2; %evaluate the function on the x values we just made