
6.3.1 Boolean algebra
Problem:
Prove the identity, using the laws of Boolean algebra. Represent one of the expressions in the basis of elementary functions:
\begin{tabular}{|c|c|c|c|c|c|c|c|c|c|c|}
\hline\( y_{1} \) & \( y_{2} \) & \( y_{3} \) & \( y_{4} \) & \( y_{5} \) & \( y_{6} \) & \( y_{7} \) & \( y_{8} \) & \( y_{9} \) & \( y_{10} \) & \( y_{11} \) \\
\hline 0 & \begin{tabular}{l}
\( a \) \\
\( \wedge b \)
\end{tabular} & \( a \) & \( a \oplus b \) & \begin{tabular}{l}
\( a \) \\
\( \vee \vee b \)
\end{tabular} & \begin{tabular}{l}
\( a \) \\
\( \downarrow b \)
\end{tabular} & \begin{tabular}{l}
\( a \) \\
\( \Leftrightarrow b \)
\end{tabular} & \( \bar{a} \) & \begin{tabular}{l}
\( a \) \\
\( \rightarrow b \)
\end{tabular} & \( a \mid b \) & 1 \\
\hline
\end{tabular}
The set of basic function numbers should include the numbers of your option. For example, for option 1 \( y_{1}, y_{11}, y_{10} \) can be taken, the missing functions are selected based on Post's completeness theorem.
\[
\begin{array}{l}
((a \wedge \bar{c}) \downarrow(b \wedge \bar{c})) \wedge((a \mid d)(\overrightarrow{b \wedge d}))= \\
=((a \mid b) \mid(a \oplus \bar{b})) \rightarrow((c \oplus d) \wedge(d \rightarrow c)), \text { option } 2 .
\end{array}
\]