Boolean idempotence

Idempotence means that, when we combine a value with itself using an operation, we get the same value back again.

In the case of the AND operation, we have:

• 0 \cdot 0 = 0
• 1 \cdot 1 = 1
• So A \cdot A = A

In the case of OR, we get:

• 0 + 0 = 0
• 1 + 1 = 1
• So A + A = A

A \cdot A = A
A + A = A