Boolean algebra and logic gates

Question 1

What are boolean variables?

Answer 1

variables with two discrete possible states

often called true and false

Question 2

What does a truth table do?

Answer 2

Shows the result of applying a logical function to all possible combinations of inputs

Question 3

What does OR mean in a boolean expression?

Answer 3

One or both inputs must be true for the output to be true

Question 4

What is the symbol for OR in a boolean expression?

Answer 4

+

Question 5

What does AND mean in a boolean expression?

Answer 5

Both of the inputs must be true for the output to be true

Question 6

What is the symbol for AND in a boolean expression?

Answer 6

.

Question 7

What does NOT mean in a boolean expression?

Answer 7

The input is inverted

Question 8

What is the symbol for NOT in boolean expression?

Answer 8

(a straight line above the input)

Question 9

What does XOR mean in a boolean expression?

Answer 9

For the output to be true one input must be true but NOT both
(exclusive or)

Question 10

What is the symbol for XOR in a boolean expression?

Answer 10

a circle with a plus sign in the middle

Question 11

What does NAND mean in a boolean expression?

Answer 11

The equivalent of an AND then a NOT

The output is true if any output is false

Question 12

What does NOR mean in a boolean expression?

Answer 12

Neither input can be true

For the output to be true both inputs must be false

Question 13

What are De Morgan’s laws used for?

Answer 13

Changing OR and NOT functions into AND and NOT functions