Replacement and substitution, Computer Engineering

Assignment Help:

Replacement and substitution:

However, equivalences allow us to change one sentence with another without affecting the meaning, it means we know already that replacing one side of an equivalence into the other will have no effect so whatever on the semantics: but it will still be true for the same models. Just assume there we have a sentence S with a sub expression A that we write like S[A]. But there if we know A≡B so we can be sure the semantics of S is unaffected because we replace A with B, i.e. S[A] ≡S[B]. 

However, there we can also use A ≡B to replace any sub expression of S that is an instance of A. But there point to be remember that an instance of a propositional expression A is a 'copy' of A when some of the propositions of have been consistently replaced by original  sub expressions, e.g. to every P has been replaced by ¬Q. So than we call this replacement a substitution, and a mapping from propositions to expressions. Through applying a substitution U to a sentence S,  we find a new sentence S.U that is an instance of S. There always Ii is easy to show that if there A ≡B so A.U ≡B.U just for any substitution U, that is. an instance of an equivalence is as well an equivalence. Thus, an equivalence A ≡B allows us to change a sentence S[A'] to a logically and fundamentally equivalent one S[B'] but if we have substitution U like that A' = A.U and B' = B.U.


Related Discussions:- Replacement and substitution

How branching takes place in instruction pipeline, How branching takes plac...

How branching takes place in Instruction pipeline. Explain with suitable examples

How does computer know that overflow has happened, Q. How does computer kno...

Q. How does computer know that overflow has happened? Illustration: Add numbers 65 and 75 in 8 bit register in signed 2's complement notation.  Here expected result is

How many methods used to control traffic flowing in-out, How many methods u...

How many methods used to control traffic flowing into and out of the network by firewall? Firewalls utilize one or more of three ways to control traffic flowing into and out of

Various connectivity option available to internet subscriber, What are the ...

What are the various connectivity options available to Internet Subscribers? Internet Connectivity Options: Internet access is perhaps one of the most admired services that

Database management system, what is time out based schemes in concurrency c...

what is time out based schemes in concurrency control

What is called when a star connected intermediate exchange, A star connecte...

A star connected intermediate exchange is known as a? A star connected intermediate exchange is termed as a Hub exchange.

Argument be passed to a subroutine in programming, How many ways can an arg...

How many ways can an argument be passed to a subroutine in programming? Ans)  An argument can be passed in two way in a programming language. They are Pass by Value and Passi

Explain two dimensional array, Explain two dimensional array In two dim...

Explain two dimensional array In two dimensional arrays, array is a pointer-to-pointer-to-data type.: at the first level, it points to a block of pointers, one for each row. Th

Subprogram or procedure level, SubProgram or Procedure Level This level...

SubProgram or Procedure Level This level consists of subroutines, procedures or subprograms. Average grain size is used at this level containing various thousands of instructio

How do we bind keys to menus for shortcuts in gimp, Make ensure that "Use d...

Make ensure that "Use dynamic keyboard shortcuts" option in "Interface" tab of Preferences dialog is enabled, then go to the menu selection you are interested in. Keeping it select

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd