2.6 Logical Operations on Bits

There are four primary logical operations we'll do with hexadecimal and binary numbers: and, or, xor (exclusive-or), and not. Unlike for the arithmetic operations, a hexadecimal calculator isn't necessary to perform these operations. It is often easier to do them by hand than to use an electronic device to compute them. The logical and operation is a dyadic[22] operation (meaning it accepts exactly two operands). These operands are individual binary bits. The and operation is:

0 and 0 = 0
               0 and 1 = 0
               1 and 0 = 0
               1 and 1 = 1

A compact way to represent the logical and operation is with a truth table. A truth table takes the form shown in Table 2-2.

Table 2-2. and Truth Table

and

0

1

0

0

0

1

0

1

This is just like the multiplication ...

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