1. I need to find the volume of a square based pyramid which one side of its base is 756ft. Its height is 481ft and the material density is 150lb/ft^3It has to be using calculus. 2. Relevant equations: I know that the formula would be 1/3*(b^2*h), but I need to use calculus to reach that formula. Basically a proof. 3. The attempt at a solution: The book gives me an example which basically answers me the whole exercise and the internet too, but I don't really get it. Look at this page and its explanation on example 2: http://tutorial.math.lamar.edu/Classes/CalcI/MoreVolume.aspx What I tried to do, because it seems logical, is sum the area of the squares as they approach infinite from 0 to its height (481ft). I don't really get it, shouldn't I just divide the pyramid in infinite squares and sum their areas to obtain the pyramid volume? Also I don't get the 2D drawing; is the length of s 2 times one side of the square?