Question

A combination of logic gates has the truth table below.

P Q Z

0 0 0

0 1 1

1 0 1

1 1 1

Which of the following combinations has this truth table?

• A.
• B.
• C.
• D.

Answer 1

Answer: (C)

Answer 2

(1) Z = $(\overline{\bar{P} + Q})$ $\begin{matrix} P & Q & Z \\ 0 & 0 & 0 \\ 0 & 1 & 0 \end{matrix}$

(2) Z = $(\overline{\bar{P}.Q})$ $\begin{matrix} P & Q & Z \\ 0 & 0 & 1 \end{matrix}$

(3) Z =$(\overline{\bar{Q}.\overline{(P + Q)}})$ $\begin{matrix} P & Q & Z \\ 0 & 0 & 0 \\ 0 & 1 & 1 \\ 1 & 0 & 1 \\ 1 & 1 & 1 \end{matrix}$

(4) Z = $( \overline { \mathrm { P } . \mathrm { Q } } )$ $\begin{matrix} P & Q & Z \\ 0 & 0 & 0 \\ 0 & 1 & 0 \\ 1 & 0 & 0 \end{matrix}$