deletions | additions       diff --git a/bits1.tex b/bits1.tex  index 09124c9..820be31 100644  --- a/bits1.tex  +++ b/bits1.tex 
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More precisely, we want to introduce two operations, \emph{sum} and \emph{multiplication}, retaining some  similarity with the usual operations of sum and product for numbers.  The numbers we are interested in are integers, which we collect in a set called   $\ZZ=\{ \ldots,-1,0,1,2, \ldots\}$, and rational numbers, which we collect in a set called $\QQ=\{ \ldots,\frac{-5}{101}, \frac{1}{2},0,3,\ldots\}$). \frac{1}{2},0,3,\ldots\}$.  \\  In the following table, we can see how to sum and multiply bits.