maybe i will sound very stupid but i don't care. This question has hammered my head for days. i had to calculate the volume of the frustum (square based) having top base side(s), bottom base side(S) and height(H).
i didn't remember the frustum volume standard formula so instead of googling for it i tried to find it my way. In my head i tried to visualize it as the sum of
1.the volume obtained by multiplication of the top base surface by the height
2.the volume obtained by HALF of the multiplication of the difference of the two areas (so SB - Sb) by the height
the final formulas would be (( S^2 - s^2 ) * h )/ 2 + s^2 * h.
now the result of this would bè different from the application of the standard formula and my question is why? what is wrong in my way of think? please help me..