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

Explanation

From the truth table we note that Y=A+B i.e, it is for OR gate (or)
`A+X=A+B=A+B.(A+barA)( :. 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