Difference between revisions of "Boolean Algebra"

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(Laws)
(AND Identities)
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<math> A.\overline{A}=0 </math>
 
<math> A.\overline{A}=0 </math>
 
The output of this equation will always be 0 as A will need to be both 1 and 0 at the same time for this logic to return a 1.
 
 
<math> A.B = B.A </math>
 
 
This equation can be written like this as it does not matter which way around the values are entered. The output will be the same.
 
 
<math> A.(B.C) = (A.B).C </math>
 
 
This equation can be written like this as all values must be equal to 1 for the output to be 1. Therefore the order in which it is written does not matter.
 
 
<math> A+(B.C) = (A.B).(A+C) </math>
 
  
 
==OR Identities==
 
==OR Identities==

Revision as of 09:36, 8 May 2018

Any equation must be within the <math> </math> tags. For Boolean alegbra the main issue is how to negate a term like:

¯a or ¯¯a+b

this can be done by adding the following around any term you wish to negate.:

<math> \overline{} </math>  

¯a

is

 <math> \overline{a} </math>

¯¯a+b

is

 <math> \overline{\overline{a}+b} </math>.

Identities

AND Identities

A=A

This equation means that the output is determined by the value of A. So if A =0, The output is 0, and vice versa.

0.A=0

Because there is a 0 in this equation, the output of this will always be 0 regardless of the value of A.

A.A=A

The output is determined by A alone in this equation. This can be simplified to just "A".

A.¯A=0

OR Identities

0+A=A

"If 0 or A goes in, A is the output"

1+A=1

"If 1 or A goes in, 1 is the output"

¯A+1=1

"If NOT A or 1 goes in, the output is 1"

¯A+A=1

"If NOT A or A goes in, the output is 1"

Laws

Commutative Law

The Commutative Law is where equations are the same no matter what way around the letters are written. For example

[math] A+B=B+A [/math]

or

[math] A.B=B.A [/math]

Laws

Associate Law

Distributive Law

The distributive law is these two equations.

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

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

Redundancy Law

¯A=¯A or ¯¯A=A

Identity Law

A+A=A

Negation Law

Equations

Solving equations is a matter of applying the laws of boolean algrebra, followed by any of the identities you can find:

Example 1

Example 2

Example 3

Example 4

Example 5

Example 6

Example 7