Lesson set of real numbers

This is a sample text of a lesson to show you the capabilities of my lesson system. Try saving this lesson (it will be saved in the development area) and then see how it looks. Then go ahead and change it!

Please do not release unfinished lessons to production! Have respect for thousands of children visiting this site and looking for help. Although I am not a control freak, abuse of any kind will not be tolerated.

To separate paragraphs, enter a double NEW LINE by pressing the ENTER key twice.
To enter nice looking formulae, enter them using the triple curly braces, like this:
x[1,2] = (-b +- sqrt( b^2-4ac ))/(2a)

<BR>
sqrt( int( 1/(1+x^2), dx, -infinity, infinity ) ) <BR>

To create graphs, use the same notation:
graph( 600, 400, -10, 10, -20, 20, x^2-4x-3, x-2, 3-x )

That's a graph 600x400 pixels, x changes from -10 to +10, y changes from -20 to 20.