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Short note: Boolean algebra

Short answer

Boolean algebra, developed by George Boole, deals with binary variables (0,1) and operations AND, OR, NOT. It simplifies logic circuits using laws like commutativity, distributivity, and De Morgan's theorems (e.g., (A·B)' = A' + B') to reduce gate count.

Write a short note on Boolean Algebra.

Boolean algebra, developed by George Boole, is the algebra of binary variables (0 and 1) with the operations AND (·), OR (+) and NOT (bar). It is used to describe and simplify digital logic circuits, so that fewer gates are needed.

Basic laws and identities:

LawAND formOR form
IdentityA⋅1=AA\cdot1=AA+0=AA+0=A
NullA⋅0=0A\cdot0=0A+1=1A+1=1
IdempotentA⋅A=AA\cdot A=AA+A=AA+A=A
ComplementA⋅Aˉ=0A\cdot\bar A=0A+Aˉ=1A+\bar A=1
CommutativeAB=BAAB=BAA+B=B+AA+B=B+A
Associative(AB)C=A(BC)(AB)C=A(BC)(A+B)+C=A+(B+C)(A+B)+C=A+(B+C)
DistributiveA(B+C)=AB+ACA(B+C)=AB+ACA+BC=(A+B)(A+C)A+BC=(A+B)(A+C)
AbsorptionA(A+B)=AA(A+B)=AA+AB=AA+AB=A

Also, double negation: Aˉˉ=A\bar{\bar A}=A.

De Morgan's theorems:

A⋅B‾=Aˉ+Bˉ,A+B‾=Aˉ⋅Bˉ\overline{A\cdot B}=\bar A+\bar B, \qquad \overline{A+B}=\bar A\cdot\bar B

Example of simplification:

Y=AB+ABˉ=A(B+Bˉ)=A⋅1=AY=AB+A\bar B=A(B+\bar B)=A\cdot1=A

Boolean expressions can be written in sum-of-products or product-of-sums form, and further simplified using Karnaugh maps.

✓ Answer checked by Claude Opus 5.5 (high effort)

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