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+8 votes

Consider the following gate network

Which one of the following gates is redundant?

  1. Gate No. 1
  2. Gate No. 2
  3. Gate No. 3
  4. Gate No. 4
in Digital Logic by | 4.8k views

So, this question's incorrect?

2 Answers

+24 votes
Best answer


                         (1)                                       (2)

o/p=w' + w'z + z'xy                                      O/p = w' +z'xy 

=w' (1+z) + z'xy

=w' +z'xy 

Both (1) and (2) giving the same output.

Hence,Option(B)Gate No. 2

selected by
+8 votes
The above circuit produces the expression w'+w'z+z'xy  which is simplified to w'(1+z) +z'xy =w'+z'xy so the gate no 2 which produces w'z is redundant as it has been eliminated in final result  

hence ans is B

@Sanjay Sharma

Sir is there any quick method to solve this?

This was a pretty easy que but for the tricky questions, quick method could be more handly.

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