Boolean algebras are structures which behave similar to a power set with complement, intersection and union. Questions regarding Boolean algebras as structures, or regarding functions defined from/to Boolean algebras fit into this tag very nicely. For Boolean logic use the tag propositional logic

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Problem 1.30 (The Maximum Principle is equivalent to the axiom of choice) (J.Bell, Boolean-valued Models and Independence Proofs, 3rd edition)

Problem 1.30 (The Maximum Principle is equivalent to the axiom of choice) (i) Let $\{a_i : i ∈ I\} ⊆ B$ satisfy $\bigvee_{i∈I} a_i = 1$. A partition of unity $\{b_i : i ∈ I\}$ in B is called a ...
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Inverse function in multi-valued logic through the Webb function

Let Webb function in multi-valued logic as $Webb(x, y) = W(x, y) = Inc(Max(x, y))$. There is a theorem about any function in any multi-valued logic can be represented through the Webb function. Then ...
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Boolean algebra proof - point me in the right direction?

I wish to formulate a proof that if $x+y = x+z$ and $xy$ = $xz$ then $y=z$. I'm just beginning my study of Boolean algebra, but is $y=z$ not self evident from the stated equations?
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Boolean Algebra on Circuits

Can I use boolean algebra to simplify electric circuits installed on buildings, establishments (etc.) using the blueprint of the buildings fluorescent lamp circuit system and electric fan circuit ...
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Knights and Knaves

A very special island is inhabited only by knights and knaves. Knights always tell the truth, and knaves always lie. You meet four inhabitants: Bozo, Marge, Bart and Zed. Bozo says," ...
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What does the complement mean as it relates to Boolean Algebra?

For a lattice to be a Boolean Algebra it must be a distributive lattice and contain complements. What does the word complement mean?
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A function whose value is either one or zero

First I apologize in advance for I don't know math's English at all and I haven't done math in almost a decade. I'm looking for a function whose "domain/ensemble of definition" would be ℝ (or maybe ...
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The cardinality of finite Boolean lattice

A book (Introduction to Lattices and Order) says that we can prove that the cardinality of any finite Boolean lattice $B$ is a power of 2 by induction on $|B|$ with the following lemma: If a lattice ...
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Simplifying Boolean Expression

I am asked to simply the following expression $$F(a,b,c) = c’ab + c’b’ + aba + b’cb + abc + c’b$$ using the Boolean identities and finding $F'(a, b, c)$ using DeMorgan’s law I have been trying for ...
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Boolean algebra - sum of products form

I have a logic circuit where the output can be represented with the following boolean expression (1)$\overline {xy}$ + x $\bar y z$ + $\overline {\bar x + z} $ + y Using truth tables I found the ...
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Semantic parsing of a sentence from “The mathematical analysis of logic” By Goerge Boole, 1847

Having the pleasure of reading some original text, I was wondering if someone can translate two small statements on the second half of page 11 from ...
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Is it possible, in Boolean Algebra, to add arbitrarily a new term to both sides of an expression?

First of all, i'm sorry for my english. I'll try to do my best to explain myself. I've been trying to look for it on the internet, but i'm not sure about the answer. I hope someone can help me here ...
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Simplifying boolean function using boolean algebra

How to simplify the following expression : A'BCD + AB'CD' + AB'CD + ABC'D + ABCD' + ABCD ? It should get AC + BCD + ABD using Kmap but using boolean algebra i am stuck no matter how i try .
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Element chasing style proof applied to Boolean algebra problem

I would like to apply an element chasing style proof to the following problem: Let $P$, $Q$ and $R$ be elements of a Boolean algebra. Prove that if $$ \tag 1 P + Q = P + R$$ and $$\tag 2 P ...
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Does a complete subalgebra A of a complete boolean B algebra always intersect all dense subsets of B?

I'm trying to show that if $(B, i)$ is the (BA) completion of any partial order $P$ and $A$ is a complete subalgebra of $B$, then $i^{-1}[A]$ is a complete suborder of $P$. Pure hunch says it's ...
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Give all Boolean algebras on the finite set

Given a finite set $X=\{1,2,3\}$, are the following all the Boolean algebras? $A_1=\{\{1\},\{2\}\},$ $A_2=\{\{1\},\{3\}\},$ $A_3=\{\{2\},\{3\}\},$ $A_4=\{\{1\},\{1,2\}\},$ $A_5=\{\{1\},\{1,3\}\},$ ...
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Simplifying Boolean Function with Karnaugh Maps

Given the boolean function f(x,y,z) = xyz + xyz' + xy'z + xy'z' + x'yz + x'y'z + x'y'z' (where x' = not x) In a three variable Karnaugh Map: ...
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Transforming statements of a query language to propositional logic

I have a custom query language which expresses containment relations between variables. Containment in this context is simply an object (A) in programming language X (java/C#/python etc: a language ...
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Boolean Algebra Simplification Help, Need AND's, OR's, NOT's only

I'm having a very hard time simplifying this: A!B!C+ABC+!A!BC+!AB!C The objective here is to simplify the equation until it can be expressed in "AND"'s "OR"'s and "NOT"'s. I have to create an ...
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If X is a subset of a complete boolean algebra, must there be a finite $Y \subset X$ s.t. sup(Y) = sup(X)?

The question came up when I was trying to prove the compactness of the stone space S(B) of a complete boolean algebra B. Using only the basic facts regarding ultrafilters and boolean algebras, I ...
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Is this boolean algebra problem solvable?

My professor is of no help at all. He's foreign and is giving assignments that are written poorly, and is teaching stuff far beyond what he's supposed to be teaching at this level. Nonetheless, he's ...
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488 views

Boolean Algebra Distributive Laws

Given that $x\cdot(y+z)=(x\cdot y)+(x\cdot z)$ and $x+(y\cdot z)=(x+y)\cdot (x+z)$, what is the name for the opposite of those rules? Say I'm trying to prove the opposite, and I need to simplify from ...
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compare 3 variables in MATLAB

I am wondering how to compare 3 variables in MATLAB, because MATLAB is comparing first 2 and then result against 3rd. To illustrate with example: (-1 == -1 == -1) ans = ...
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Is there a name for the set $\{T,F\}$?

Is there a name for the set containing the two Boolean values, i.e. $\{T,F\}$? I am also thinking if $B = \{T,F\}$, and $B^n = \underbrace{B \times B\times B ... \times B}_n$, then is there a proper ...
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Boolean Simplification: (A+C)(!A+B)(B+C) = BC

How might I solve this? I can't find any problem similar to this, and I always end up with the wrong terms. If (AB) = 0 and (A+B) = 1, prove that (A+C)(!A+B)(B+C) = BC
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Boolean Algebra

There seems to be some discrepancy between my answer and the solution's. Can somebody please tell me what I have done wrong? Thanks! $$\begin{align} \left(A \lor B\right) \land \left(B \lor C\right) ...
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toggle boolean and more

Recently I used this to toggle a Boolean value, b being the current value and self.status being the result self.status = (b-1)*(b-1) This rather than use an if ...
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calculating number of boolean functions

I would just like to clarify if I am on the right track or not; I have these questions: Consider the Boolean functions $f(x,y,z)$ in three variables such that the table of values of $f$ contains ...
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is the following a Boolean Algebra?

Boolean Algebra: $$D_{30}=\{n:n\mid30\}= \{1,2,3,5,6,10,15,30\}$$ I don't know how to test that this is a boolean algbra (a BA is a distributive lattice with $T,F$ in which every element has a ...
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Proving if equations are products of XOR

I have to prove analytically to see if these equations are exclusively or. $$A⊕ A=0$$ Do I solve this by using the truth table? ...
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Generating Input Binary Combination Dynamically

this is probably right forum to post this question I am currently working on a application where there is a requirement to generate binary combination of input signals in a truth table. The signal ...
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Show that $x \wedge y = x \iff x \vee y= y$ using the following properties

Suppose $L$ is a set with binary operations $\wedge$ and $\vee$, along with the special $T$ and $F$ (for an $x,y,z \in L$) such that the following rules hold: $x\wedge T=x$; $x\vee y=T$ ...
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How to prove distributivity in Boolean Rings

A Boolean ring is a ring which all of its elements are idempotent, i.e. $a ^{2}=a$. I know that If we interpret multiplication and addition in such a ring, as meet and joint respectively, then Boolean ...
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Boolean simplification

So I am giving this expression D +B’C’ + CD’ +A B’C and I ask to simplify it When working through it I get D+B'C'+CD'+AB'C D'(A'B'+CD'+AB) D'(A'B'+A(B'+B)) D'(A'B'+AC') D'(B'+A) Am I on the right ...
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Boolean Function

A Boolean expression is given: (A B)’ + B C’ +A’ C = F. Construct the logical circuit and draw the timing diagram of the output F. I am not sure where to start.
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Boolean Simplification

I'm having some trouble getting a handle with this course. We are starting Boolean algebra and my professor wants us simplify the following: (AB)'+(A'+B')'= (AB)'+BC+A'B'C'= I am assuming the "()" ...
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Adjoint for functor involving Boolean rings

Let $R$ be a a commutative ring with a unit element, then one can associate to $R$ a Boolean ring $B(R)$, as in this text by Bergman, last line of page 594. (I guess this is a very classical thing. ...
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Linearly separate a cube

I am facing the problem of the linear separability of a three dimensional cube. Let's take the opposite vertexes of the cube as $(0, 0, 0), (1, 1, 1)$. It is possible to split it with a plane in two ...
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Terminology question; inverse vs complement in Boolean algebra

This was said at a lecture I attended: $e$ is neutral element for operation $*$ if $\forall x (x*e=x \wedge e*x = x)$. So, for example 0 is n. e. for disjunction and 1 is n. e. for ...
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Help at solving boolean function.

I`m having some difficulties solving a boolean expression (I am converting it to CNF form). The expression is: $$F = (Q_1 \to P1 \land \lnot P_2) \lor Q_1 \land P_2 \lor P_1$$ So i do not know, ...
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Non-principal ideal in Boolean ring

Does anyone know a simple example of a Boolean ring with a non-principal ideal? Every finitely generated ideal in a Boolean ring is principal, hence such an ideal cannot be finitely generated...
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Given a state transformation matrix and a state vector, how to find the total number of changes for each individual element.

I have a vector of binary variables, $s$ representing a state at some point in time, and a transformation matrix $T$. The initial state is $s_0$. $s_n = Ts_{n-1}$ Given a number of transformations, ...
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Boolean Logical Algebra - Prove 4 nor gates to an xnor gate.

Need to reach the following conclusion (or maybe its the premise?) AB + A'B' = F http://upload.wikimedia.org/wikipedia/commons/thumb/f/f8/XNOR_using_NOR.svg/256px-XNOR_using_NOR.svg.png
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Infinite boolean sequence

I was given the following problem: Let $V_1, V_2, \dots$ be an infinite sequence of Boolean variables. For each natural number $n$, define a proposition $F_n$ according to the following rules: ...
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Boolean algebra spectrum

The first-order spectrum of a theory, is the set of cardinalities of its finite models. Finite models of Boolean algebras are informally n-dimensional cubes, therefore boolean algebra spectrum is the ...
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Boolean Algebra - Truth Table

X'Y'Z' + XYZ I have the equation above (Boolean Algebra truth table), and as I know, if I get x' and the value of x is 0, the value will change to 1. But Y' with the top bar being higher, what ...
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Number of canonical expressions

There is a question: What is the number of canonical expressions that can be developed over a 3-valued boolean algebra? I was trying to solve this. Canonical expression is the combination of ...
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Boolean Algebra Manipulation/Simplification

I have come across a couple questions while doing my digital logic work. 1) Is it possible to simplify these, while keeping each a product of sums? (I'm leaning towards no--the only way I could see ...
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Which of the following representations of Karnaugh map is 'better'?

I usually come across two representations of Karnaugh maps in books and on the web as shown in the figure. The difference is whether the higher order variables are on the rows or on the columns. I ...
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Boolean circuits and digraphs

It is well known that connecting NAND gates allows the construction of arbitrary circuits. Furthermore, a NAND gate can be represented as a digraph with four vertices (in order, the two inputs, the ...