A Level Computer Science OCR Practice Exam

The Commutation law allows us to switch which operators?

1. AND and OR

2. AND only

3. XOR only

4. None

The correct answer is: AND and OR

The Commutation law, a fundamental principle in Boolean algebra, states that the order of certain operations can be switched without affecting the outcome. Specifically, it applies to the operations of AND and OR. This means that for two variables, A and B, the following identities hold true: - A AND B is equivalent to B AND A. - A OR B is equivalent to B OR A. This feature of the commutation law allows flexibility when simplifying logical expressions or designing digital circuits. Understanding this law is crucial for students as it aids in manipulating logical statements efficiently, whether in theoretical work or practical applications such as circuit design or programming. The other options either restrict the application of the commutation law to only one operator or incorrectly state that it doesn't apply at all. Therefore, the correct answer reflects the ability to interchange both AND and OR operators without altering the result of the expression.