Boolean double negation

Double negation is the idea that if we have a NOT of a NOT, we can simplify it to just the thing itself. So, for example, \overline{\overline{A}} simplifies to just A.

\overline{\overline{A}} = A

This works with larger expressions, too. For example:

This is sometimes also called the double complement law.

flashcards

QuestionAnswer
What is Boolean double negation?If we have a NOT of a NOT, we can simplify it to just the thing itself.
How do you simplify \overline{\overline{A}}?It simplifies to A; \overline{\overline{A}} = A.
How do you simplify \overline{\overline{A + B}}?It simplifies to A + B; \overline{\overline{A + B}} = A + B.
How do you simplify \overline{\overline{A \cdot B}}?It simplifies to A \cdot B; \overline{\overline{A \cdot B}} = A \cdot B.
How do you simplify \overline{\overline{\overline{A} + \overline{B}}}?It simplifies to \overline{A} + \overline{B}; \overline{\overline{\overline{A} + \overline{B}}} = \overline{A} + \overline{B}.
What is another name for the double negation law?It is sometimes called the double complement law.