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+%
+% quadrieren.tex -- Quadrieren
+%
+% (c) 2021 Prof Dr Andreas Müller, OST Ostschweizer Fachhochschule
+%
+\bgroup
+\begin{frame}[t]
+\setlength{\abovedisplayskip}{5pt}
+\setlength{\belowdisplayskip}{5pt}
+\frametitle{Quadrieren}
+\vspace{-20pt}
+\begin{columns}[t,onlytextwidth]
+\begin{column}{0.40\textwidth}
+\begin{block}{Problem}
+\( g = g_1 = g_2 \)
+$\Rightarrow$
+Tangente
+\\
+\uncover<2->{{\color{red}ohne Analysis!}}
+\end{block}
+\begin{center}
+\includegraphics[width=\textwidth]{../../buch/chapters/90-crypto/images/elliptic.pdf}
+\end{center}
+\end{column}
+\begin{column}{0.56\textwidth}
+\uncover<3->{%
+\begin{block}{Lösung}
+Finde $h\in G$ derart, dass
+\begin{align*}
+g(t)
+&=
+tg + (1-t)h
+\\
+\uncover<4->{%
+\begin{pmatrix}X(t)\\Y(t)\end{pmatrix}
+&=
+t\begin{pmatrix}x_g\\y_g\end{pmatrix}
++(1-t) \begin{pmatrix}x_h\\y_h\end{pmatrix}
+}
+\end{align*}
+\uncover<5->{eingesetzt
+\[
+p(t)
+=
+Y(t)^2+X(t)Y(t)-X(t)^3-aX(t)-b
+=
+0
+\]}%
+\uncover<6->{%
+Nullstellen $0$ (doppelt) und $1$ hat:}
+\[
+\uncover<7->{p(t) = c(t^3-t)}
+\]
+\uncover<8->{Koeffizientenvergleich: einfachere Gleichungen für $x_h$ und $y_h$}
+\end{block}}
+\end{column}
+\end{columns}
+\end{frame}
+\egroup