# Boolean Algebra Proof w/ Venn Diagrams?

Discussion in 'Homework Help' started by Darkmyr, Apr 13, 2013.

1. ### Darkmyr Thread Starter New Member

Apr 13, 2013
2
0
Okay, I really don't understand this at all and my teacher is horrible at explaining stuff and expects everyone to get it after one example.
Can someone explain as simply as possible how to prove these 3 using Venn Diagrams, and if you could draw them out for me in Paint that would be helpful.

1.
A+BC = (A+B)(A+C)

2.
A(B+C) = AB+AC

3.
(BC+AC')(AB+AC) = 0

2. ### DerStrom8 Well-Known Member

Feb 20, 2011
2,428
1,328
Sorry, that's not going to happen. We are not here to do your homework for you. We need to see some attempt of yours on the problem first, and we'll help you along from there. Do not ask us to just hand over the answers though.

Matt

3. ### Darkmyr Thread Starter New Member

Apr 13, 2013
2
0
Thats understandable..
I'll be more specific
In A+BC = (A+B)(A+C), when I distributed, and then tried the diagram, it worked and matched with the other side but how come in say x(x+y)=x, it works w/o distributing?

And can someone explain what 0 would be? nothing shaded or everything shaded? b

4. ### WBahn Moderator

Mar 31, 2012
17,757
4,800
If youi shade everything for some function F blue and shade everything for some function G red, and then are tasked to show H in green where

H = F+G

Then any place that is either blue or red woiuld be colored green, whereas if

H=F*G

Then only those places that are both blue and red would be colored green.

If, in the latter example, there were no places that were both blue and red then you would have no place that would be shaded green that that would mean that H=0.

For you x(x+y) case, it's not a matter of it "working without distributing". Shade your two reagions , (x) and (x+y), slightly differently (crosshatch one way for the first and another way for the second). Now identify the intersection, namely x(x+y). What do you notice about the relationship between x and the intersection of x(x+y)? Can you describe this relationship in words?