141. Which one of the following is not a valid rule of Boolean algebra?

1. 1. A + 1 = 1

   
   
   

   2. A = A

   
   
   

   3. AA = A

   
   
   

   4. A + 0 = A

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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142. The domain of expression ABCD + AB + CD + B is—

1. 1. A and D

   
   
   

   2. B only

   
   
   

   3. A, B, C, D

   
   
   

   4. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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143. The Boolean expression A BC D is—

1. 1. Sum term

   
   
   

   2. Product term

   
   
   

   3. A literal term

   
   
   

   4. Always 1

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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144. The Boolean expression A + B + C is—

1. 1. Sum term

   
   
   

   2. A literal term

   
   
   

   3. A product term

   
   
   

   4. A complement term

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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145. Find output of given circuit—
     
     
     

1. 1. f = AB + BCD

   
   
   

   2. f = A(B + C + D)

   
   
   

   3. f = AC + BCD

   
   
   

   4. f = AB + AC + BCD

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   
   

   Correct Option: D

   NA

   
   

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