PythagoreanTheorem

The PythagoreanTheorem is attributed to the Greek philosopher and mathematician Pythagoras who lived in the 6th century B.C. The theorem states a relationship between the lengths of the sides of a right triangle. It says:

The sum of the squares of the length the sides of a right triangle is equal to the square of the length of the hypotenuse.

Visually, the theorem can be illustrated as follows:

Given a right triangle, with sides a and b and hypotenuse c, (Figure 1)

                                                     / l

                                                   /   l

                                      c         /      l 

                                              /        l 

                                           /           l  b

                                        /              l

                                     /________________ l

                                           a

                                      Figure 1

the hypotenuse is the side opposite the right (90 degree) angle in a right triangle.

Then, c^2 = a^2 + b^2, or c = sqrt(a^2 + b^2).

Certain sets of 3 integers are useful to remember as being Pythagorean triples, that is, they are possible lengths of the sides of a right triangle. For example:

                     a                     b                       c

                     3                     4                       5

                     9                    12                      15

The PythagoreanTheorem is an important tool in the study of TrigonometricFunctions.

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Poser: (3,4,5) is a pythagorean triplet since 3^2 + 4^2 = 5^2. Which positive integers are not part of a pythagorean triplet?