191. A switching function
     f (A, B, C, D) = A′B′CD + A′BC′D + A′BCD + AB′C′D + AB′CD
     can also be written as—

1. 1. Σ m (1, 3, 5, 7, 9)

   
   
   

   2. Σ m (3, 5, 7, 9, 11)

   
   
   

   3. Σ m (3, 5, 9, 11, 13)

   
   
   

   4. Σ m (5, 7, 9, 11, 13)

   
   
   

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1. View Hint View Answer Discuss in Forum

   Σ m implies minterm which are SOP form (already in that form in question) Hence:
   
   Hence alternative (B) is the correct answer.

   Correct Option: B

   Σ m implies minterm which are SOP form (already in that form in question) Hence:
   
   Hence alternative (B) is the correct answer.

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192. Identify the operation performed by the gate circuit shown in figure—
     

1. 1. AND

   
   
   

   2. OR

   
   
   

   3. NAND

   
   
   

   4. NOR

   
   
   

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1. View Hint View Answer Discuss in Forum

   
   Y = [(AB)′]′ = AB i.e., equivalent to AND gate. Hence alternative (A) is the correct answer.

   Correct Option: A

   
   Y = [(AB)′]′ = AB i.e., equivalent to AND gate. Hence alternative (A) is the correct answer.

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193. The output of a gate Y = AB + A′B′, where A and B are inputs, what is that gate?

1. 1. EX-NOR

   
   
   

   2. NAND

   
   
   

   3. EX-OR

   
   
   

   4. All of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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194. The minimum number of NAND gates required to realize EX-OR gate are—

1. 1. 5

   
   
   

   2. 4

   
   
   

   3. 3

   
   
   

   4. 6

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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195. The output of a gate is zero if and only if when all the inputs are high. What is that gate?

1. 1. AND gate

   
   
   

   2. OR gate

   
   
   

   3. NAND gate

   
   
   

   4. NOR gate

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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