Page 108 - Bebop to The Boolean Boogie An Unconventional Guide to Electronics Fundamentals, Components, and Processes
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BooleanAlgebra      89

             The Second Distributive Rule
                In standard arithmetic, the addition operator will not distribute over the
             multiplication operator because it has a lower pre~edence:~


                                    6 + (5 x 2)  f  (6 + 5) x (6 + 2)


                However, Boolean Algebra is special in this case. Even though the  I  (OR)
             operator has lower precedence than the &a (AND) operator, it will still
             distribute over the &a  operator; this is known as the second distributive rule
             (Figure 9-9).


                        y=a 1  (b&c)                                     y = (a  I  b) & (a  I  G)

                   S’





                                 OR
                    G
                         &
                       AND                                            c/I/
                                                                           OR





              a  b  c      (b&c)     Y                      a b c        (aIb)  (a  I       Y
              000            0       0                      000            0        0       0
              0  0   1       0       0                      0   0  1       0         1      0
              0   1  0       0       0                      0   1  0        1       0       0
              0  1   1       1        1                     0   1  1        1        1      1
              1   0  0       0        1                      1  0  0        1        1      1
              1   0  1       0        1                      1  0  1        1        1      1
              1   1  0       0        1                      1  1  0        1        1      1
              1   1  1       1        1                      1  1  1        1        1      1
                                                                                            f




                                   Figure 9-9. The second distributive rule



             4 Note that the symbol z shown in the equation indicates “is not equal to.”
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