Question

@DanJS

Answer 1

It is the sum of rectangles formed under the curve between the function and the x axis. The definite integral is the exact value for the area as you let the width of the boxes go to zero, or in other words, the number of boxes used in approximating the area goes to infinitly many.

Answer 2

and thats it?? i thouhgt it was asking for something else, thanks(:

Answer 3

That is what that whole summation formula is, It is the function evaluated at x (the height of the box) times delta x ( the width of the box), and you let the number of boxes go to ininity.