25
Cavalieri’s Principle tells us the volumes of these pyramid equal one another.
2 Initial steps To begin with, we need to define the volume of cube and cuboid. 2.1 Cube
ܽ 3 , where
ܽ is the length of one side.
We postulate the volume of a cube is
2.2 Cuboid
ሺܽ ൈ ܾ ൈ ܿሻ . Then
Suppose three values a, b, c which are the sides of a cuboid
ܽ  ܾ  ܿ . According to our axiom, the
we form a cube with the side length of
volume of this cube would be ሺܽ  ܾ  ܿሻ 3 : ሺܽ  ܾ  ܿሻ 3 ൌ ܽ 3  ܾ 3  ܿ 3  3ܾܽܿሺܽ  ܾ  ܿሻ ֜ ሺܽ  ܾ  ܿሻ 3  ܽ 3  ܾ 3  ܿ 3 ൌ ሺܽ  ܾሻ 3  ሺܽ  ܿሻ 3  ሺܾ  ܿሻ 3  6ܾܽܿ ൌ ሺܽ  ܾሻ3  ሺܽ  ܿሻ3  ሺܾ  ܿሻ3  6ܾܽܿ Then we divide the big cube into 3 cubes which have a 3 , b 3 , c 3 cubes intersecting. Therefore, the remaining pieces are 6 cuboids; the volume of each would be ܽ ൈ ܾ ൈ ܿ . Accordingly, the volume of a cuboid would be : ܪ ݄݁݅݃ ݐ ൈ ܮ ݁݊݃ ݐ ݄ ൈ ܹ݅݀ ݐ ݄ . 3 Implementation In this section we try to work out the volume of some common shapes using the introduced principle. 3.1 Pyramid Let’s define “perfect pyramid”. The base of a perfect pyramid is a rectangle and the height is one of its sides.
Made with FlippingBook - Online Brochure Maker