2.6. Conclusion

Try these first

1. 1.

   What is a tautology? Provide an example.

   Hint

   Consider statements that encompass all truth values.

2. 2.

   What does it mean for two statements to be logically equivalent?

   Hint

   Think about when two statements yield the same outcome.

3. 3.

   What is a tautology?

   • A statement that is always false
   • A statement that is sometimes true
   • A statement that is always true

   Hint

   Remember that it consistently holds no matter what.

4. 4.

   True or False: A contradiction can ever be true in some cases.

   • True
   • False

   Hint

   Think about the definition of contradiction.

5. 5.

   Prove using logical identities that 'not(p or q)' is equivalent to 'not p and not q'.

   Hint

   Utilize the relevant identity confidently.

6. 6.

   Show how to deduce a complex expression using standard logical identities.

   Hint

   Decide which identities apply to your transformation.