Basic Integration: finding the area under a curve by a GeoGebra applet - fully interactive

With the following GeoGebra applet, you can find out the area under a curve by integration -  interactively. 

All you need to do is  to move the two sliders to points of your choice and tick the checkbox for answer to appear.

The function used in this case is a quadratic function.

Enjoy, learn and prosper!