The truth table given below correspond to the logic gate \begin{tabular}{cc|c} $\mathrm{A}$ & $\mathrm{B}$ & $\mathrm{X}$ \\ \hline 0 & 0 & 1 \\ 1 & 0 & 0 \\ 0 & 1 & 0 \\ 1 & 1 & 0 \end{tabular}

The given gate is a NOR gate. The output is high, when all inputs are low. Truth Table: \begin{tabular}{|c|c|c|} \hline $\mathbf{A}$ & $\mathbf{B}$ & $\mathbf{Y}$ \\ \hline 0 & 0 & 1 \\ \hline 1 & 0 & 0 \\ \hline 0 & 1 & 0 \\ \hline 1 & 1 & 0 \\ \hline \multicolumn{2}{|c|} { Logic Symbols } \\ \hline \end{tabular}
Boolean expression: $\overline{\mathrm{A}+\mathrm{B}}=\mathrm{Y}$