BO
O
LEAN
ALG
EBRA
2
Boolean Algebra
I will take an umbrella with me if it is raining
or the weather forecast is bad
3
Boolean Algebra
I will take an umbrella with me if it is raining
or the weather forecast is bad
4
Boolean Algebra
I will take an umbrella with me if it is raining
or the weather forecast is bad
A Simple Proposition
5
Boolean Algebra
I will take an umbrella with me if it is raining
or the weather forecast is bad
Propositions may be TRUE or FALSE, are functions of other
propositions, and connected by logical connections (AND, OR,
NOT)
6
Boolean Algebra
I will take an umbrella with me if it is raining
or the weather forecast is bad
Truth Table
7
Boolean Algebra
George Boole, the mathematician, developed
boolean algebra to simplify the handling of
complex connectives.
Boolean Algebra uses ordinary algebraic
notation, and 1 for True and 0 for False.
8
Boolean Algebra
I will take an umbrella with me if it is raining
or the weather forecast is bad
U = R + F
Boolean equation
Raining Bad Forecast Umbrella
0 0 0
0 1 1
1 0 1
1 1 1
9
Boolean Algebra
If I do not take the car then I will take an
umbrella if it is raining or the weather forecast
is bad
10
Boolean Algebra
If I do not take the car then I will take an
umbrella if it is raining or the weather forecast
is bad
11
Boolean Algebra
If I do not take the car then I will take an
umbrella if it is raining or the weather forecast
is bad
12
Boolean Algebra
If I do not take the car then I will take an
umbrella if it is raining or the weather forecast
is bad
U = C’. (W + R)
13
Boolean Algebra
U = C’. (W + R)
If I do not take the car then I will take an
umbrella if it is raining or the weather forecast
is bad
14
Boolean Identities
Basic boolean identities.
X + 0 = X X * 1 = X X + 1 = 1
X * 0 = 0 X + X = X X * X = X
X + X = 1 X = X X * X = 0
15
Basic Laws of Boolean Algebra
The basic laws of boolean algebra are:
Commutative Law:
X + Y = Y + X XY = YX
Associative Law:
X+(Y+Z) = (X+Y)+Z X(YZ)=(XY)Z
Distributive Law:
X(Y+Z) = XY + XZ X+YZ = (X+Y)(X+Z)
16
Boolean Laws and Identities
Reduce the boolean function F = X Y Z + X Y + X Y Z
17
Boolean Laws and Identities
Reduce the boolean function F = X Y Z + X Y + X Y Z
F = X Y (Z + Z) + X Y (Distributive and Commutative Laws)
18
Boolean Laws and Identities
Reduce the boolean function F = X Y Z + X Y + X Y Z
F = X Y (Z + Z) + X Y (Distributive and Commutative Laws)
F = X Y (Z + Z) + X Y (Identity)
= 1
19
Boolean Laws and Identities
Reduce the boolean function F = X Y Z + X Y + X Y Z
F = X Y (Z + Z) + X Y (Distributive and Commutative Laws)
F = X Y (Z + Z) + X Y (Identity)
= 1
F = X Y + X Y
20
Boolean Laws and Identities
Reduce the boolean function F = X Y Z + X Y + X Y Z
F = X Y (Z + Z) + X Y (Distributive and Commutative Laws)
F = X Y (Z + Z) + X Y (Identity)
= 1
F = X Y + X Y
F = (X + X) Y (Distributive Law)
21
Boolean Laws and Identities
Reduce the boolean function F = X Y Z + X Y + X Y Z
F = X Y (Z + Z) + X Y (Distributive and Commutative Laws)
F = X Y (Z + Z) + X Y (Identity)
= 1
F = X Y + X Y
F = (X + X) Y (Distributive Law)
F = (X + X) Y (Identity)
= 1
22
Boolean Laws and Identities
Reduce the boolean function F = X Y Z + X Y + X Y Z
F = X Y (Z + Z) + X Y (Distributive and Commutative Laws)
F = X Y (Z + Z) + X Y (Identity)
= 1
F = X Y + X Y
F = (X + X) Y (Distributive Law)
F = (X + X) Y (Identity)
= 1
F = Y
23
Advanced Boolean Laws
Here are some advanced laws of boolean algebra that
can be directly applied to the reduction of boolean
functions.
X + X Y = X
X Y + X Y = X
X + X Y = X + Y
X (X + Y) = X
(X + Y)(X + Y) = X
X (X + Y) = X

Boolean algebra

  • 1.
  • 2.
    2 Boolean Algebra I willtake an umbrella with me if it is raining or the weather forecast is bad
  • 3.
    3 Boolean Algebra I willtake an umbrella with me if it is raining or the weather forecast is bad
  • 4.
    4 Boolean Algebra I willtake an umbrella with me if it is raining or the weather forecast is bad A Simple Proposition
  • 5.
    5 Boolean Algebra I willtake an umbrella with me if it is raining or the weather forecast is bad Propositions may be TRUE or FALSE, are functions of other propositions, and connected by logical connections (AND, OR, NOT)
  • 6.
    6 Boolean Algebra I willtake an umbrella with me if it is raining or the weather forecast is bad Truth Table
  • 7.
    7 Boolean Algebra George Boole,the mathematician, developed boolean algebra to simplify the handling of complex connectives. Boolean Algebra uses ordinary algebraic notation, and 1 for True and 0 for False.
  • 8.
    8 Boolean Algebra I willtake an umbrella with me if it is raining or the weather forecast is bad U = R + F Boolean equation Raining Bad Forecast Umbrella 0 0 0 0 1 1 1 0 1 1 1 1
  • 9.
    9 Boolean Algebra If Ido not take the car then I will take an umbrella if it is raining or the weather forecast is bad
  • 10.
    10 Boolean Algebra If Ido not take the car then I will take an umbrella if it is raining or the weather forecast is bad
  • 11.
    11 Boolean Algebra If Ido not take the car then I will take an umbrella if it is raining or the weather forecast is bad
  • 12.
    12 Boolean Algebra If Ido not take the car then I will take an umbrella if it is raining or the weather forecast is bad U = C’. (W + R)
  • 13.
    13 Boolean Algebra U =C’. (W + R) If I do not take the car then I will take an umbrella if it is raining or the weather forecast is bad
  • 14.
    14 Boolean Identities Basic booleanidentities. X + 0 = X X * 1 = X X + 1 = 1 X * 0 = 0 X + X = X X * X = X X + X = 1 X = X X * X = 0
  • 15.
    15 Basic Laws ofBoolean Algebra The basic laws of boolean algebra are: Commutative Law: X + Y = Y + X XY = YX Associative Law: X+(Y+Z) = (X+Y)+Z X(YZ)=(XY)Z Distributive Law: X(Y+Z) = XY + XZ X+YZ = (X+Y)(X+Z)
  • 16.
    16 Boolean Laws andIdentities Reduce the boolean function F = X Y Z + X Y + X Y Z
  • 17.
    17 Boolean Laws andIdentities Reduce the boolean function F = X Y Z + X Y + X Y Z F = X Y (Z + Z) + X Y (Distributive and Commutative Laws)
  • 18.
    18 Boolean Laws andIdentities Reduce the boolean function F = X Y Z + X Y + X Y Z F = X Y (Z + Z) + X Y (Distributive and Commutative Laws) F = X Y (Z + Z) + X Y (Identity) = 1
  • 19.
    19 Boolean Laws andIdentities Reduce the boolean function F = X Y Z + X Y + X Y Z F = X Y (Z + Z) + X Y (Distributive and Commutative Laws) F = X Y (Z + Z) + X Y (Identity) = 1 F = X Y + X Y
  • 20.
    20 Boolean Laws andIdentities Reduce the boolean function F = X Y Z + X Y + X Y Z F = X Y (Z + Z) + X Y (Distributive and Commutative Laws) F = X Y (Z + Z) + X Y (Identity) = 1 F = X Y + X Y F = (X + X) Y (Distributive Law)
  • 21.
    21 Boolean Laws andIdentities Reduce the boolean function F = X Y Z + X Y + X Y Z F = X Y (Z + Z) + X Y (Distributive and Commutative Laws) F = X Y (Z + Z) + X Y (Identity) = 1 F = X Y + X Y F = (X + X) Y (Distributive Law) F = (X + X) Y (Identity) = 1
  • 22.
    22 Boolean Laws andIdentities Reduce the boolean function F = X Y Z + X Y + X Y Z F = X Y (Z + Z) + X Y (Distributive and Commutative Laws) F = X Y (Z + Z) + X Y (Identity) = 1 F = X Y + X Y F = (X + X) Y (Distributive Law) F = (X + X) Y (Identity) = 1 F = Y
  • 23.
    23 Advanced Boolean Laws Hereare some advanced laws of boolean algebra that can be directly applied to the reduction of boolean functions. X + X Y = X X Y + X Y = X X + X Y = X + Y X (X + Y) = X (X + Y)(X + Y) = X X (X + Y) = X

Editor's Notes

  • #6 http://www.doc.ic.ac.uk/~dfg/hardware/HardwareLecture01.pdf
  • #7 http://www.doc.ic.ac.uk/~dfg/hardware/HardwareLecture01.pdf
  • #8 http://www.doc.ic.ac.uk/~dfg/hardware/HardwareLecture01.pdf
  • #9 http://www.doc.ic.ac.uk/~dfg/hardware/HardwareLecture01.pdf