The logic circuit and its truth table are given, what is the gate X in the diagram

Explanation

From the truth table we not that `Y=A+B`
i.e., it is for OR gate (or)
`A+X=A+B=A+B.(A+barA)(because A+barA=1)`
then, `A+X=A+B.A+B.barA=A.(1+B)+barA.B=A+barA.B`
So `X=barA.B`, which is AND gate with inputs as `barA` and B