Question

List the 10 most important logical identities

Answer 1

1. Identity \((\mathrm{A}=\mathrm{A})\)
2. Contradiction \((A \neq \sim A)\)
3. Tautology \((A \vee \sim A)\)
4. Negation \((A \rightarrow \sim A)\)
5. Conjunction \((A \wedge B \rightarrow A, A \wedge B \rightarrow B)\)
6. Disjunction \((A \vee B \rightarrow A, A \vee B \rightarrow B)\)
7. Conditional \((A \rightarrow B, \sim B \rightarrow \sim A)\)
8. Biconditional \((A \leftrightarrow B, A \rightarrow B\) and \(B \rightarrow A)\)
9. De Morgan's Laws \((\sim(A \wedge B)=\sim A \vee \sim B, \sim(A \vee B)=\sim A \wedge \sim B)\)
10. Absorption Laws \((A \wedge(A \vee B)=A, A \vee(A \wedge B)=A)\)