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Diffstat (limited to 'test/phase5/exact-cases-contradiction.tex')
| -rw-r--r-- | test/phase5/exact-cases-contradiction.tex | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/test/phase5/exact-cases-contradiction.tex b/test/phase5/exact-cases-contradiction.tex new file mode 100644 index 0000000..cf08a8e --- /dev/null +++ b/test/phase5/exact-cases-contradiction.tex @@ -0,0 +1,45 @@ +\begin{proposition}\label{cases_exact} + Let $A$ be a set. + $A=A$. +\end{proposition} +\begin{proof} + \begin{byCase} + \caseOf{$A=\emptyset$.} + Follows. + \caseOf{$A=\{A\}$.} + Follows. + \caseOf{$A=A$.} + Follows. + \end{byCase} +\end{proof} + +\begin{proposition}\label{by_contradiction_exact} + Let $A$ be a set. + $A=A$. +\end{proposition} +\begin{proof} + Suppose not. + Follows. +\end{proof} + +\begin{proposition}\label{arbitrary_contradiction_exact} + Let $A$ be a set. + Suppose $A\neq A$. + Then $A=A$. +\end{proposition} +\begin{proof} + Contradiction. +\end{proof} + +\begin{proposition}\label{omitted_case_exact} + Let $A$ be a set. + $A=A$. +\end{proposition} +\begin{proof} + \begin{byCase} + \caseOf{$A=A$.} + Omitted. + \caseOf{$A\neq A$.} + Follows. + \end{byCase} +\end{proof} |
