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CHAPTER 10 / BASIC TECHNOLOGY OF THE INTELLIGENT COMMUNICATION SYSTEM I I 3
Example 2:
Example 3:
Example 4:
A logical expression is true, false, or true or false. A logical expression with
value "T" is called a tautology and is valid. A logical expression with value "F' is
a contradiction and is unsatisfactory. A logical expression of value "T" or "F" is
satisfactory.
10.3.3 Evaluation of a Logical Expression by Means
of a Semantic Tree
Consider the logical expression P composed of atomic formulas p {, p 2, p n. P can
be represented asP(p ltp 2,...,p n).
An evaluation method in which both "T" and "F" are assigned to each atomic
formula is the semantic tree method:
In this method, an evaluation proceeds in finite steps by assigning'T' and "F' to
each atomic formula. Some examples follow.
Example 1:
This expression is a tautology and is valid.
