diff --git a/slides/chapter-09.en.md b/slides/chapter-09.en.md
index 2d571cd..59e84de 100644
--- a/slides/chapter-09.en.md
+++ b/slides/chapter-09.en.md
@@ -205,12 +205,25 @@ $\left\lbrace x \mid \mathrm{frequency} …
@slide(layout=task)
@task-number
-8
+8a
@title
Typesetting mathematics
@content
-* Reinclude `eingabefile.tex`, `textsatz.tex`, and `mathematik.tex` by adjusting the `\includeonly` command in `l2kurz.tex`.
-* Compile the entire project once again.
-* Have a look at chapter 4: Insert your personal favourite **formula** in section 4.5.
+Code up the following formulas in the file `exercises/maths/math-formulas.raw.tex`.
+
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+
+@slide(layout=task)
+
+@task-number
+8b
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+@title
+Typesetting mathematics
+
+@content
+Code up the following formulas in the file `exercises/maths/math-formulas.raw.tex`.
+
+
diff --git a/svg/chapter-09/task-a-crop.svg b/svg/chapter-09/task-a-crop.svg
index 0945ff3..322865f 100644
--- a/svg/chapter-09/task-a-crop.svg
+++ b/svg/chapter-09/task-a-crop.svg
@@ -1,5 +1,5 @@
-
diff --git a/svg/chapter-09/task-a.tex b/svg/chapter-09/task-a.tex
index 48fea61..ad1ee3e 100644
--- a/svg/chapter-09/task-a.tex
+++ b/svg/chapter-09/task-a.tex
@@ -14,19 +14,23 @@
\begin{center}
-\textbf{Fallbeschleunigung in Deutschland}
+\textbf{Fallbeschleunigung in Deutschland} \\
+(Gravitational acceleration)
$$9,81\,\frac{m}{s^2}$$ \\
~ \\
-\textbf{pq-Formel}
+\textbf{pq-Formel} \\
+(Formula to solve quadratic equations)
$$x_{1,2} = - \frac{p}{2} \pm \sqrt{\left(\frac{p}{2}\right)^2 - q}$$ \\
~ \\
-\textbf{Mitternachtsformel}
+\textbf{Mitternachtsformel} \\
+(Another formula to solve quadratic equations)
$$x_{1,2} = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$ \\
~ \\
-\textbf{Catalansche Zahlen}
+\textbf{Catalansche Zahlen} \\
+(Catalan numbers)
\begin{equation*} C_n = \frac{1}{n+1} {2n \choose n} = \frac{(2n)!}{(n+1)!n!} \end{equation*}
\end{center}
diff --git a/svg/chapter-09/task-b-crop.svg b/svg/chapter-09/task-b-crop.svg
index 9845f17..97e3ea5 100644
--- a/svg/chapter-09/task-b-crop.svg
+++ b/svg/chapter-09/task-b-crop.svg
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diff --git a/svg/chapter-09/task-b-orig.svg b/svg/chapter-09/task-b-orig.svg
index 764606e..1d91e52 100644
--- a/svg/chapter-09/task-b-orig.svg
+++ b/svg/chapter-09/task-b-orig.svg
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diff --git a/svg/chapter-09/task-b.tex b/svg/chapter-09/task-b.tex
index 77b210c..41124c0 100644
--- a/svg/chapter-09/task-b.tex
+++ b/svg/chapter-09/task-b.tex
@@ -14,11 +14,13 @@
\begin{center}
-\textbf{Definition der Fakultät}
+\textbf{Definition der Fakultät} \\
+(Definition of factorial)
$$n! = \prod_{i=1}^{n} i$$ \\
~ \\
-\textbf{Menge aller ungeraden natürlichen Zahlen}
+\textbf{Menge aller ungeraden natürlichen Zahlen} \\
+(Set of all odd natural numbers)
$$\{ x \mid x \in \mathds{N}, \mathrm{ungerade}(x) \}$$
~ \\