"Truth tables with conjunctions or disjunctions"

Truth Tables Overview

  • A truth table is a mathematical table used to determine the truth or falsity of a logical expression based on all possible truth values of its variables.

Key Concepts

  • Variables:

    • Use variables, like p and q, to represent statements.

  • Negation:

    • Denoted as \sim

    • When p is true, \sim p is false and vice versa.

    • Rule: \sim p has the opposite truth value of p .

  • Disjunction:

    • Denoted as p \lor q (read as "p or q")

    • It is true when at least one of p or q is true.

    • Rule: p \lor q is false only when both p and q are false.

  • Conjunction:

    • Denoted as p \land q (read as "p and q")

    • It is false when either p or q is false.

    • Rule: p \land q is true only when both p and q are true.

Completing a Truth Table

  1. Negation for Variable p:

    • Create a column for \sim p and apply the negation rule.

    • Example values:

      • If p = T , then \sim p = F

      • If p = F , then \sim p = T

  2. Negation for Variable q:

    • Create a column for \sim q in the same manner as above.

  3. Disjunction and Conjunction Columns:

    • Combine the truth values for \sim p and \sim q using the disjunction and conjunction rules.

    • Example:

      • For \sim q \lor \sim p , evaluate all combinations of truth values for both variables.

Truth Table Structure Example

p

q

\sim p

\sim q

\sim q \lor \sim p

T

T

F

F

F

T

F

F

T

T

F

T

T

F

T

F

F

T

T

T

Conclusion

  • The final answer of the truth table focuses on the column derived from combining negations, disjunctions, and conjunctions.

  • Important to note the relationships between the truth values for accurate logical conclusions.