# Switching Circuits Questions and Answers – Boolean Algebra Basic Theorems

This set of Switching Circuits Multiple Choice Questions & Answers (MCQs) focuses on “Boolean Algebra Basic Theorems”.

1. Evaluate the boolean expression A + 0.
a) A
b) 0
c) A’
d) 1

Explanation: The answer to the above question can be verified using the following truth table.

A A + 0
0 0
1 1

From the above truth table, it can be verified that A + 0 = A.

2. Evaluate the Boolean expression A.1.
a) 1
b) A’
c) A
d) 0

Explanation: The answer to the above question can be verified using the following truth table.

A A.1
0 0
1 1

From the above table it can be verified that A.1 = A.

3. The Boolean expression A + 1 evaluates to A.
a) True
b) False

Explanation: The answer to the above question can be verified using the following truth table.

A A + 1
0 1
1 1

From the above table it can be verified that A + 1 = 1. Hence the answer is False.

4. The Boolean expression A.0 evaluates to 0.
a) True
b) False

Explanation: The answer to the above question can be verified using the following truth table.

A A.1
0 0
1 0

From the above table it can be verified that A.0 = 0. Hence the answer is True.

5. Evaluate the Boolean expression A + A.
a) A
b) 1
c) 0
d) A’

Explanation: The answer to the above question can be verified using the following truth table.

A A + A
0 0
1 1

From the above table it can be verified that A + A = A.

6. Evaluate the Boolean expression A.A.
a) A
b) 1
c) 0
d) A’

Explanation: The answer to the above question can be verified using the following truth table.

A A.A
0 0
1 1

From the above table it can be verified that A.A = A.

7. Evaluate the Boolean expression A.A’.
a) A
b) 1
c) 0
d) A’

Explanation: The answer to the above question can be verified using the following truth table.

A A’ A.A’
0 1 0
1 0 1

From the above table it can be verified that A.A’ = 0.

8. Evaluate the Boolean expression A + A’.
a) A
b) 1
c) 0
d) A’

Explanation: The answer to the above question can be verified using the following truth table.

A A’ A + A’
0 1 1
1 0 1

From the above table it can be verified that A + A’ = 1.

9. Evaluate the Boolean expression (A’)’.
a) A
b) 1
c) 0
d) A’

Explanation: The answer to the above question can be verified using the following truth table.

A A’ (A’)’
0 1 0
1 0 1

From the above table it can be verified that (A’)’ = A.

10. Evaluate the Boolean expression A + B + C’ + D +1.
a) A
b) 1
c) 0
d) C’

Explanation: As any Boolean expression ORed with 1 result in 1, the answer is 1.
In other words, using the property A + 1 = 1, we get the answer.

Sanfoundry Global Education & Learning Series – Switching Circuits.

To practice all areas of Switching Circuits, here is complete set of 1000+ Multiple Choice Questions and Answers.

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