Question

The figure shows two `NAND` gates followed by a `NOR` gate. The system is equivalent to the following logic gate

A. `OR`
B. `AND`
C. `NAND`
D. None of these

Answer 1

Correct Answer - B
The truth table of the circuit is given as
`|(A,B,C,X=bar(AB),Y=bar(BC),Z=bar(X+Y)),(0,0,0,1,1,0),(1,0,0,1,1,0),(0,0,1,1,1,0),(1,0,1,1,1,0),(0,1,0,1,1,0),(1,1,0,0,1,0),(1,1,1,0,0,1)|`
Output `Z` of single three input gate is that ot `AND` gate.