# And without and, or without or, xor without xor

Discussion in 'Homework Help' started by hayesdanny, Mar 22, 2012.

1. ### hayesdanny Thread Starter New Member

Mar 22, 2012
2
0
And with And

Or without Or

Xor with Xor

These all work correctly the problem I am having is explaining it and justifying its operation using demorgans law. Any help would be appreciated

2. ### MrChips Moderator

Oct 2, 2009
18,711
5,943
The simple solution is to draw the truth tables and compare, for example,

draw the truth table for X = A AND B

Compare with the truth table for Y = NOT ( (NOT A) OR (NOT B) )

3. ### hayesdanny Thread Starter New Member

Mar 22, 2012
2
0
thanks for the reply, I have checked the truth tables and they are the same the problem I am having is putting the solutions into a algorithm and explaining them so how did you get
Y = NOT ( (NOT A) OR (NOT B) )

4. ### Georacer Moderator

Nov 25, 2009
5,154
1,281
The method is formal. If two functions have the same truth table, they are equivalent.

I find DeMorgan's law overestimated in proving equivalencies.