Colored graph (Known function)

I would like to create a graph similar to this one: (I already know the Mathematical function)

I can draw the function, but to color the right side and left side was for me hard to achieve.

Anybody has an Idea how can I do that?!

Answer 1

[SSM]

Use the patch() function.

Example:

%%% Create sample data
x = 0:1:100;
y = sin(x);
plot(x,y)
patch([x fliplr(x)], [y max(ylim)*ones(size(y))], 'r') %%% Patch the area above the sine curve red
patch([x fliplr(x)], [y min(ylim)*ones(size(y))], 'r') %%% Patch the area below the sine cutve blue
legend() %%% Add the legend here