deletions | additions       diff --git a/section_Solutions_and_hints_for__.tex b/section_Solutions_and_hints_for__.tex  index c221062..cfa1a8f 100644  --- a/section_Solutions_and_hints_for__.tex  +++ b/section_Solutions_and_hints_for__.tex 
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\begin{itemize}  \item $\textrm{NOT }((\textrm{NOT }a) \textrm{ AND }(\textrm{NOT }b)) = a\textrm{ OR }b$  \item $\textrm{NOT }((\textrm{NOT }a)\textrm{ OR }(\textrm{NOT }b)) = a\textrm{ AND }b$  \item $(\textrm{NOT }a)\textrm{ XOR }(\textrm{NOT }b) }b)$  and a\textrm{ $a\textrm{  XOR }b$ have the same truth table. \end{itemize}  \textbf{Exercise 6.}\\  $\textrm{NOT }a = a+1$\\