diff --git a/semester3/ti-compact/parts/04_computability.tex b/semester3/ti-compact/parts/04_computability.tex
index 8c23fa2..1bfd353 100644
--- a/semester3/ti-compact/parts/04_computability.tex
+++ b/semester3/ti-compact/parts/04_computability.tex
@@ -159,6 +159,13 @@ or the condition can be restated such that only $L(M)$ is described by it.
 For a more formal proof of that condition, simply show that the implication holds
 
 
+Another result (not formally proven in the script, but there is a proof by intimidation) that can come in useful, especially when trying to show $L \notin \cL_{RE}$ is:
+\rmvspace
+\begin{align*}
+    L, L^C \in \cL_{RE} \Longleftrightarrow L \in \cL_R
+\end{align*}
+
+
 \stepcounter{subsection}
 \subsection{The method of the Kolmogorov-Complexity}
 \inlinetheorem The problem of computing the Kolmogorov-Complexity $K(x)$ for each $x$ is algorithmically unsolvable.
diff --git a/semester3/ti-compact/ti-compact.pdf b/semester3/ti-compact/ti-compact.pdf
index c832fa4..623c2c5 100644
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