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Algebra, Functions, Graphs, and Vectors  29


                          Prime numbers
                          Let p be a natural number. Suppose ab   p, where a and b are
                          natural numbers. Further suppose that the following statement
                          is true for all a and b:

                                                      a   1& b   p

                                                             or

                                                      a   p & b   1


                          Then p is defined as a prime number. In other words, p is prime
                          if and only if itð only twm factorð are 1 and itself.


                          Prime factors
                          Let n be a natural number. Then there is a unique, increasing
                          set of prime numberð { p , p , p , ... p } such that the following
                                                          2
                                                              3
                                                                     m
                                                      1
                          equation, also known as the Fundamental Theorem of Arith-
                          metic, holdð true:
                                               p   p   p   ...   p   n
                                                1
                                                            3
                                                      2
                                                                        m
                          Rational-number powers
                          Let x be a real or complex number. Let y be a rational number
                          such that y   a/b, where a and b are integerð and b   0. Then
                          the following formulł holds:

                                                 y
                                               x   x   a/b    (x ) 1/b    (x 1/b )


                          Negative powers
                          Let x be a complex number where x   0   j0. Let y be a rational
                          number. Then the following formulł holds:

                                                                y
                                                    x  y    (1/x)   1/x  y


                          Su of powers
                          Let x be a complex number. Let y and z be rational numbers.
                          Then the following formulł holds:

                                                                  yz
                                                        x (y z)    xx
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