Help me make a Circuit?

Question

If I have 3 switches that turn on the same lightbulb how would the circuit look?

I am thinking

x'(y+z) + y'(x+z) + z'(x+y)

That does not fully work correctly.

Answer 1

depends on how you want them to work.

All in parallel, it becomes a logical OR, that is, the light turns on if any one of the switches is on.

All in series, it becomes a logical AND that is, the light turns on if all three of the switches are on.

edit

Read up on parallel and series circuits, wikpedia is good.

"how would the circuit look if it holds all the posible ways I can turn on or off the light by pressing the switches"

Have no idea what this means!

.

Answer 2

You need a 3 input Exclusive OR gate. I don't know how to write something with a bar on top, so I will write it down in words:

(x*ybar + xbar*y)bar*z + (x*ybar + xbar*y)*zbar

where ybar is the inverse of y etc, + stands for OR, * stands for AND