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of A when some of the propositions of have been consistently replaced by original  sub expressions, e.g. to every P has been replaced by ¬Q. So than we call this replacement a substitution, and a mapping from propositions to expressions.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

Write a c++ program to explain three specific classes, Make a base class ca...

Make a base class called figure that store the dimensions of several geometrical objects and compute their areas. Explain a function set_dim( ),a standard member  function and show

What is compact disk rom, Q. What is Compact Disk ROM? Both audio CD an...

Q. What is Compact Disk ROM? Both audio CD and CD-ROM (compact disk read-only memory) share similar technology. Main difference is that CD-ROM players are more rugged and have

State the approaches to organizing stored program control, Determine the ap...

Determine the approaches to organizing stored program control There are 2 approaches to organizing stored program control: 1.  Centralized: In this control, all control equi

Staircase, What is the aim of a stair case light is controlled by two switc...

What is the aim of a stair case light is controlled by two switches one at the top of the stairs and another at the bottom of the stair

What do you mean by embedded system, It is a mixture of hardware and softwa...

It is a mixture of hardware and software to perform needed task

What are the issues of software development, What are the issues of softwar...

What are the issues of software development One of main issues in software development today is quality. Software must be properly documented and implemented. The notion of sof

How to fix an asic-based design from easiest to most extreme, How to fix an...

How to fix an ASIC-based design from easiest to most extreme? There are different ways to fix an ASIC-based design as given below: Initially, assume some reviews fundamentally.

What is directory, What is Directory?   The device directory or simply ...

What is Directory?   The device directory or simply called as directory records information-such as name, location, size, and type for all files on that certain partition. The

Explain about the prepurchase interaction activity, Explain about the Prepu...

Explain about the Prepurchase Interaction activity. Prepurchase Interaction: This interaction for consumers comprises three activities: • Product or service search and di

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