Boolean OR zero

If we have an expression like:

…then for any value of , we are ORing it with 0. If we and anythign with 0, then we get that thing back.

We know that, because of the OR truth table:

• 1 OR 0 = 1
• 0 OR 0 = 0, so:
• A OR 0 = A
• (because the first number above is what we end up getting)

In short:

We can use this to simplify boolean algebra!

We can replace anywhere we see with