Proved to mathematical relationships is true
I know it is silly but I need your help
and I want to summaries or exercises for this section (Logic Algebra and Sets)
This is an exercise in carefully following the definitions. Look in your book for the precise definitions of these operations, then write them out. For instance, on the first one, start with
$\displaystyle \{x\in \{y\in A\mid y\notin B\}\mid x\notin C\}$
and go from there.