Fundamental theorem of calculus relates the two important concepts of calculus :  Differentiation and  Integration. For a continuous function  , and a function , the selection for every    holds if and only if

                                                          ,             .

In the following applet,  you can select a function from the  drop-down  menu . The variables A, B, C, D for the function can be changed by the sliders.

In the view panel at the bottom when you move the sliders for a function left to right, the first graph show the area to be computed and the second graph displays its values .the third graph is the derivative of the second.