Lecture 11: Complex Conditions

Activity:

Please simplify the following conditionals so that the ! operator is only used as !=. As you complete these problems, keep in mind De Morgan's laws. Here A and B represent variables.

1. !(A != B)

2. !((A == 1) || (A == 4))

3. !((A >= 4) && (B < 2))

4. !((A != 5) || (B == 6))

5. !((A != 5) || (A == 5))
(Note: Can this conditional evaluate to true?)

6. !((A != 5) && (A == 5))
(Note: Can this conditional evaluate to false?)

Conditionals that never evaluate to true are called contradictions. Conditionals that always evaluate to true are called tautologies.