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DeMorgan's Identities (single bit)

x y ~x ~y x & y ~(x & y) ~x | ~y ~~x
0 0 1 1 0 1 1 0
0 1 1 0 0 1 1 0
1 0 0 1 0 1 1 1
1 1 0 0 1 0 0 1

This verifies the first version of DeMorgan's Law below and the idempotent law (~~x = x) for single bit values x and y.

          ~(x & y) = (~x) | (~y)

          ~(x | y) = (~x) & (~y)

          ~~x = x
     

These DeMorgan's Laws for single bit values are analogous the following version applied to logical statements p, q with values true corresponding to 1 and false corresponding to 0:

The following are logical statements equivalent

Symbolically

      NOT (p AND q) =  (NOT p) OR (NOT q)
   

and similarly

      NOT (p OR q) = (NOT p) AND (NOT q)
   


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