The correct truth table for the following logic circuit is :

Solution

Physics sir · 2 steps

Name each gate's output, then feed both into the OR: Y is Ā + AB, which is Ā + B.

1. Read the gates. The top branch sends A through a NOT gate, giving Ā. The bottom branch sends A and B through an AND gate, giving AB. The OR gate combines the two, so Y = Ā + AB.

   Y = Ā + AB = (Ā + A)(Ā + B) = Ā + B

   A B	Ā	AB	Y = Ā + AB
   0 0	1	0	1
   0 1	1	0	1
   1 0	0	0	0
   1 1	0	1	1

2. So. The output column reads 1, 1, 0, 1. Y is 0 only when A = 1 and B = 0, which is the table in option (b).

The idea to keep. For any gate circuit, write the output of every gate in terms of A and B, then fill a truth table column by column. Simplify with Ā + AB = Ā + B when it helps.

Answer from the NTA final answer key. Solution by PrepWiser.