# Pythagorean theorem

### Let's get started on the lesson the Pythagorean theorem

## Did you know .....?

## Chou pei suan ching

A Chinese astronomical and mathematical treatise called chou pei suan ching. (The arthimetical Classic of the Gnomon and the circular paths of Heaven) , possibly predating Pythagoras, gives a statement of a geometrical deminstration of the Pythagorean theorem.

## Real life examples using the Pythagorean theorem

1) what size tv should you buy? Mr James saw an advertisement of a tv in the newspaper where it is mentioned that the tv is 16 inches high and 14 inches wide. Calculate the diagonal length of its screen for Mr. James. By using Pythagoras theorem it can be calculated as ,

(16)2+(14)2=

256+196=c2

Radical 452=c

21inches approx =c

(16)2 + (10)2 =

256 + 100 = c2

Radical 356 = c

18 inches approx = c

(18)2 + (b)2 =

(B)2 = 900 _ 324 =

B =radical 576

=24 inches

## How to proof the Pythagorean trheorem

In mathematics, the Pythagorean theorem, also known as Pythagoras theorem, is a fundemetal relation in Euclidean geometry among the three sides of a right triangle. (It states that the square of the hypotenuse ( the side oppose to the right triangle) is equal to the sum of the squares of the other two sides.

## Some pictures about the lesson

## OTHER WAYS PROVING THE PYTHGOREAN THEOREM

Professor R. Smullyan in his book 5000 B.C. and other philosophical fantasies tells of an experiment he ran in one of his geometry classes. He drew a right triangle on the board with squares on the hypotenuse and legs and observed the fact that the square on the hypotenuse had a larger area than either of the other two squares.Then he asked,"suppose these three squares were made of beaten gold, and you were offered either the one large square or the two small squares. Which square would you choose?"Interestingly enough, about half of the class opted for the one large square and half for the two small squares. Both groups were equally amazed when told that it would make no difference

http://youtu.be/I8-bnZh8Zuc