% % taylor.tex -- Repetition Taylot-Reihen % % (c) 2021 Prof Dr Andreas Müller, OST Ostschweizer Fachhochschule % Erstellt durch Roy Seitz % % !TeX spellcheck = de_CH \bgroup \begin{frame}[t] \setlength{\abovedisplayskip}{5pt} \setlength{\belowdisplayskip}{5pt} \frametitle{Beispiel $\sin(x)$} \ifthenelse{\boolean{presentation}}{\vspace{-20pt}}{\vspace{-8pt}} \begin{block}{Taylor-Approximationen von $\sin(x)$} \begin{align*} p_{ \only<1>{0} \only<2>{1} \only<3>{2} \only<4>{3} \only<5>{4} \only<6>{5} \only<7->{n} }(x) &= \uncover<1->{0} \uncover<2->{+ x} \uncover<3->{+ 0 \frac{x^2}{2!}} \uncover<4->{- 1 \frac{x^3}{3!}} \uncover<5->{+ 0 \frac{x^4}{4!}} \uncover<6->{+ 1 \frac{x^5}{5!}} \uncover<7->{+ \ldots} \uncover<8->{ = \sum_{k=0}^{n/2} (-1)^{2k + 1}\frac{x^{2k+1}}{(2k+1)!} } \end{align*} \end{block} \begin{center} \begin{tikzpicture}[>=latex,thick,scale=1.3] \draw[->] (-5.0, 0.0) -- (5.0,0.0) coordinate[label=$x$]; \draw[->] ( 0.0,-1.5) -- (0.0,1.5); \clip (-5,-1.5) rectangle (5,1.5); \draw[domain=-4:4, samples=50, smooth, blue] plot ({\x}, {sin(180/3.1415968*\x)}) node[above right] {$\sin(x)$}; \uncover<1|handout:0>{ \draw[domain=-4:4, samples=2, smooth, red] plot ({\x}, {0}) node[above right] {$p_0(x)$};} \uncover<2|handout:0>{ \draw[domain=-1.5:1.5, samples=2, smooth, red] plot ({\x}, {\x}) node[below right] {$p_1(x)$};} \uncover<3|handout:0>{ \draw[domain=-1.5:1.5, samples=2, smooth, red] plot ({\x}, {\x}) node[below right] {$p_2(x)$};} \uncover<4>{ \draw[domain=-3:3, samples=50, smooth, red] plot ({\x}, {\x - \x*\x*\x/6}) node[above right] {$p_3(x)$};} \uncover<5|handout:0>{ \draw[domain=-3:3, samples=50, smooth, red] plot ({\x}, {\x - \x*\x*\x/6}) node[above right] {$p_4(x)$};} \uncover<6|handout:0>{ \draw[domain=-3.9:3.9, samples=50, smooth, red] plot ({\x}, {\x - \x*\x*\x/6 + \x*\x*\x*\x*\x/120}) node[below right] {$p_5(x)$};} \uncover<7|handout:0>{ \draw[domain=-3.9:3.9, samples=50, smooth, red] plot ({\x}, {\x - \x*\x*\x/6 + \x*\x*\x*\x*\x/120}) node[below right] {$p_6(x)$};} \uncover<8-|handout:0>{ \draw[domain=-4:4, samples=50, smooth, red] plot ({\x}, {\x - \x*\x*\x/6 + \x*\x*\x*\x*\x/120 - \x*\x*\x*\x*\x*\x*\x/5040}) node[above right] {$p_7(x)$};} \end{tikzpicture} \end{center} \end{frame} \begin{frame}[t] \setlength{\abovedisplayskip}{5pt} \setlength{\belowdisplayskip}{5pt} \frametitle{Taylor-Reihen} \ifthenelse{\boolean{presentation}}{\vspace{-20pt}}{\vspace{-8pt}} \begin{block}{Polynom-Approximationen von $f(t)$} \begin{align*} p_n(t) &= f(0) \uncover<2->{ + f' (0) t } \uncover<3->{ + f''(0)\frac{t^2}{2} } \uncover<4->{ + \ldots + f^{(n)}(0) \frac{t^n}{n!} } \uncover<5->{ = \sum_{k=0}^{n} f^{(k)} \frac{t^k}{k!} } \end{align*} \end{block} \uncover<6->{ \begin{block}{Erste $n$ Ableitungen von $f(0)$ und $p_n(0)$ sind gleich!}} \begin{align*} \uncover<6->{ p'_n(t) } & \uncover<7->{ = f'(0) + f''(0)t + \mathcal O(t^2) } &\uncover<8->{\Rightarrow}&& \uncover<8->{p'_n(0) = f'(0)} \\ \uncover<9->{ p''_n(t) } & \uncover<10->{ = f''(0) + \mathcal O(t) } &\uncover<11->{\Rightarrow}&& \uncover<11->{ p''_n(0) = f''(0) } \end{align*} \end{block} \uncover<12->{ \begin{block}{Für alle praktisch relevanten Funktionen $f(t)$ gilt:} \begin{align*} \lim_{n\to \infty} p_n(t) = f(t) \end{align*} \end{block} } \end{frame} \begin{frame}[t] \setlength{\abovedisplayskip}{5pt} \setlength{\belowdisplayskip}{5pt} \frametitle{Beispiel $e^t$} \ifthenelse{\boolean{presentation}}{\vspace{-20pt}}{\vspace{-8pt}} \begin{block}{Taylor-Approximationen von $e^{at}$} \begin{align*} p_{ \only<1>{0} \only<2>{1} \only<3>{2} \only<4>{3} \only<5>{4} \only<6>{5} \only<7->{n} }(t) &= 1 \uncover<2->{+ a t} \uncover<3->{+ a^2 \frac{t^2}{2}} \uncover<4->{+ a^3 \frac{t^3}{3!}} \uncover<5->{+ a^4 \frac{t^4}{4!}} \uncover<6->{+ a^5 \frac{t^5}{5!}} \uncover<7->{+ a^6 \frac{t^6}{6!}} \uncover<8->{+ \ldots = \sum_{k=0}^{n} a^k \frac{t^k}{k!}} \\ & \uncover<9->{= \exp(at)} \end{align*} \end{block} \begin{center} \begin{tikzpicture}[>=latex,thick,scale=1.3] \draw[->] (-4.0, 0.0) -- (4.0,0.0) coordinate[label=$t$]; \draw[->] ( 0.0,-0.5) -- (0.0,2.5); \clip (-3,-0.5) rectangle (3,2.5); \draw[domain=-4:1, samples=50, smooth, blue] plot ({\x}, {exp(\x)}) node[above right] {$\exp(t)$}; \uncover<1|handout:0>{ \draw[domain=-4:4, samples=12, smooth, red] plot ({\x}, {1}) node[below right] {$p_0(t)$};} \uncover<2|handout:0>{ \draw[domain=-4:1.5, samples=10, smooth, red] plot ({\x}, {1 + \x}) node[below right] {$p_1(t)$};} \uncover<3|handout:0>{ \draw[domain=-4:1, samples=50, smooth, red] plot ({\x}, {1 + \x + \x*\x/2}) node[below right] {$p_2(t)$};} \uncover<4>{ \draw[domain=-4:1, samples=50, smooth, red] plot ({\x}, {1 + \x + \x*\x/2 + \x*\x*\x/6}) node[below right] {$p_3(t)$};} \uncover<5|handout:0>{ \draw[domain=-4:0.9, samples=50, smooth, red] plot ({\x}, {1 + \x + \x*\x/2 + \x*\x*\x/6 + \x*\x*\x*\x/24}) node[below left] {$p_4(t)$};} \uncover<6|handout:0>{ \draw[domain=-4:0.9, samples=50, smooth, red] plot ({\x}, {1 + \x + \x*\x/2 + \x*\x*\x/6 + \x*\x*\x*\x/24 + \x*\x*\x*\x*\x/120}) node[below left] {$p_5(t)$};} \uncover<7|handout:0>{ \draw[domain=-4:0.9, samples=50, smooth, red] plot ({\x}, {1 + \x + \x*\x/2 + \x*\x*\x/6 + \x*\x*\x*\x/24 + \x*\x*\x*\x*\x/120 + \x*\x*\x*\x*\x*\x/720}) node[below left] {$p_6(t)$};} \uncover<8-|handout:0>{ \draw[domain=-4:0.9, samples=50, smooth, red] plot ({\x}, {1 + \x + \x*\x/2 + \x*\x*\x/6 + \x*\x*\x*\x/24 + \x*\x*\x*\x*\x/120 + \x*\x*\x*\x*\x*\x/720 + \x*\x*\x*\x*\x*\x*\x/5040}) node[below left] {$p_7(t)$};} \end{tikzpicture} \end{center} \end{frame} \egroup