\documentclass[a4paper,12pt,]{book}
\usepackage{graphicx}
\usepackage[inner=1.3cm, outer=1.3cm, top=2cm, bottom=2cm, bindingoffset=1cm]{geometry}
\usepackage[utf8]{inputenc}
\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{mathtools}
\begin{document}
\title{Chapter 3}
\author{Akor Eleojo Rachel}
\maketitle
Consider the Linear Multi-step Method:
\begin{equation}
\begin{split}
y(x) =& \alpha_{0}(x)y_{n} + h\bigg[\beta_{0}(x)f_{n}+\beta_{1}(x)f_{n+1}+\beta_{\frac{3}{2}}(x)f_{n+\frac{3}{2}}+\beta_{2}(x)f_{n+2}+\beta_{\frac{5}{2}}(x)f_{n+\frac{5}{2}}+\beta_{3}(x)f_{n+3}+\beta_{\frac{7}{2}}(x)f_{n+\frac{7}{2}} \\ =\ &+\beta_{4}(x)f_{n+4}+\beta_{\frac{9}{2}}(x)f_{n+\frac{9}{2}}\bigg]
\end{split}
\end{equation}
\begin{equation}
A=\begin{bmatrix}
1 & {x_n} & {{x_n}^{2}} & {{x_n}^{3}} & {{x_n}^{4}} & {{x_n}^{5}} & {{x_n}^{6}} & {{x_n}^{7}} & {{x_n}^{8}} & {{x_n}^{9}}\\
0 & 1 & 2 {x_n} & 3 {{x_n}^{2}} & 4 {{x_n}^{3}} & 5 {{x_n}^{4}} & 6 {{x_n}^{5}} & 7 {{x_n}^{6}} & 8 {{x_n}^{7}} & 9 {{x_n}^{8}}\\
0 & 1 & 2 {x_{n+1}} & 3 {{x_{n+1}}^{2}} & 4 {{x_{n+1}}^{3}} & 5 {{x_{n+1}}^{4}} & 6{{x_{n+1}}^{5}} & 7 {{x_{n+1}}^{6}} & 8 {{x_{ n+1}}^{7}} & 9 {{x_{n+1}}^{8}}\\
0 & 1 & 2 {x_{n+\frac{3}{2}}} & 3 {{x_{n+\frac{3}{2}}}^{2}}& 4 {{x_{n+\frac{3}{2}}}^{3}} & 5 {{x_{n+\frac{3}{2}}}^{4}} & 6 {{x_{n+\frac{3}{2}}}^{5}} & 7 {{x_{n+\frac{3}{2}}}^{6}} & 8 {{x_{n+\frac{3}{2}}}^{7}} & 9 {{x_{n+\frac{3}{2}}}^{8}}\\
0 & 1 & 2 {x_{n+2}}& 3 {{x_{n+2}}^{2}} & 4 {{x_{n+2}}^{3}} & 5 {{x_{n+2}}^{4}} & 6 {{x_{ n+2}}^{5}} & 7 {{x_{n+2}}^{6}} & 8 {{x_{n+2}}^{7}} & 9 {{x_{n+2}}^{8}}\\
0 & 1 & 2 {x_{n+\frac{5}{2}}} & 3 {{x_{n+\frac{5}{2}}}^{2}} & 4 {{x_{n+\frac{5}{2}}}^{3}} & 5{{x_{n+\frac{5}{2}}}^{4}} & 6 {{x_{n+\frac{5}{2}}}^{5}} & 7 {{x_{n+\frac{5}{2}}}^{6}} & 8 {{x_{n+\frac{5}{2}}}^{7}} & 9 {{x_{n+\frac{5}{2}}}^{8}}\\
0 & 1 & 2 {x_{n+3}} & 3 {{x_{n+3}}^{2}} & 4 {{x_{n+3}}^{3}} & 5 {{x_{n+3}}^{4}} & 6 {{x_{ n+3} }^{5}} & 7 {{x_{n+3}}^{6}} & 8 {{x_{n+3}}^{7}} & 9 {{x_{n+3}}^{8}}\\
0 & 1 & 2 {x_{n+\frac{7}{2}}} & 3 {{x_{n+\frac{7}{2}}}^{2}} & 4 {{x_{n+\frac{7}{2}}}^{3}} & 5 {{x_{n+\frac{7}{2}}}^{4}} & 6 {{x_{n+\frac{7}{2}}}^{5}} & 7 {{x_{n+\frac{7}{2}}}^{6}} & 8 {{x_{n+\frac{7}{2}}}^{7}} & 9 {{x_{n+\frac{7}{2}}}^{8}}\\
0 & 1 & 2 {x_{n+4}}& 3 {{x_{n+4}}^{2}} & 4 {{x_{n+4}}^{3}} & 5 {{x_{n+4}}^{4}} & 6{{x_{ n+4} }^{5}} & 7 {{x_{n+4}}^{6}} & 8 {{x_{n+4}}^{7}} & 9 {{x_{n+4}}^{8}}\\
0 & 1 & 2 {x_{n+\frac{9}{2}}} & 3 {{x_{n+\frac{9}{2}}}^{2}} & 4 {{x_{n+\frac{9}{2}}}^{3}} & 5 {{x_{ n+\frac{9}{2}}}^{4}} & 6 {{x_{n+\frac{9}{2}}}^{5}} & 7 {{x_{n+\frac{9}{2}}}^{6}} & 8 {{x_{n+\frac{9}{2}}}^{7}} & 9 {{x_{n+\frac{9}{2}}}^{8}}
\end{bmatrix}
\end{equation}
Replacing: {\large$x_{n}, x_{n+\frac{3}{2}}, x_{n+2}, x_{n+\frac{5}{2}}, x_{n+3}, x_{n+\frac{7}{2}}, x_{n+4}, x_{n+\frac{9}{2}}$}\\
with: $x_{n+1}-h, x_{n+1}+\frac{1}{2}h, x_{n+1}+h, x_{n+1}+\frac{3}{2}h, x_{n+1}+2h, x_{n+1}+\frac{5}{2}h, x_{n+1}+3h, x_{n+1}+\frac{7}{2}h$\\
we obtain:
\begin{equation}
\label{mat}
B=\begin{bmatrix}
1 & {x_{n+1}-h} & {{(x_{n+1}-h)}^{2}} & {{(x_{n+1}-h)}^{3}} & {{(x_{n+1}-h)}^{4}} & {{(x_{n+1}-h)}^{5}} & {{(x_{n+1}-h)}^{6}} & {{(x_{n+1}-h)}^{7}} & {{(x_{n+1}-h)}^{8}} & {{(x_{n+1}-h)}^{9}}\\
0 & 1 & 2 {(x_{n+1}-h)} & 3 {{(x_{n+1}-h)}^{2}} & 4 {{(x_{n+1}-h)}^{3}} & 5 {{(x_{n+1}-h)}^{4}} & 6 {{(x_{n+1}-h)}^{5}} & 7 {{(x_{n+1}-h)}^{6}} & 8 {{(x_{n+1}-h)}^{7}} & 9 {{(x_{n+1}-h)}^{8}}\\
0 & 1 & 2 {x_{n+1}} & 3 {{x_{n+1}}^{2}} & 4 {{x_{n+1}}^{3}} & 5 {{x_{n+1}}^{4}} & 6{{x_{n+1}}^{5}} & 7 {{x_{n+1}}^{6}} & 8 {{x_{ n+1}}^{7}} & 9 {{x_{n+1}}^{8}}\\
0 & 1 & 2 {(x_{n+1}+\frac{1}{2}h)} & 3 {{(x_{n+1}+\frac{1}{2}h)}^{2}}& 4 {{(x_{n+1}+\frac{1}{2}h)}^{3}} & 5 {{(x_{n+1}+\frac{1}{2}h)}^{4}} & 6 {{(x_{n+1}+\frac{1}{2}h)}^{5}} & 7 {{(x_{n+1}+\frac{1}{2}h)}^{6}} & 8 {{(x_{n+1}+\frac{1}{2}h)}^{7}} & 9 {{(x_{n+1}+\frac{1}{2}h)}^{8}}\\
0 & 1 & 2 {(x_{n+1}+h)}& 3 {{(x_{n+1}+h)}^{2}} & 4 {{(x_{n+1}+h)}^{3}} & 5 {{(x_{n+1}+h)}^{4}} & 6 {{(x_{n+1}+h)}^{5}} & 7 {{(x_{n+1}+h)}^{6}} & 8 {{(x_{n+1}+h)}^{7}} & 9 {{(x_{n+1}+h)}^{8}}\\
0 & 1 & 2 {(x_{n+1}+\frac{3}{2}h)} & 3 {{(x_{n+1}+\frac{3}{2}h)}^{2}} & 4 {{(x_{n+1}+\frac{3}{2}h)}^{3}} & 5{{(x_{n+1}+\frac{3}{2}h)}^{4}} & 6 {{(x_{n+1}+\frac{3}{2}h)}^{5}} & 7 {{(x_{n+1}+\frac{3}{2}h)}^{6}} & 8 {{(x_{n+1}+\frac{3}{2}h)}^{7}} & 9 {{(x_{n+1}+\frac{3}{2}h)}^{8}}\\
0 & 1 & 2 {(x_{n+1}+2h)} & 3 {{(x_{n+1}+2h)}^{2}} & 4 {{(x_{n+1}+2h)}^{3}} & 5 {{(x_{n+1}+2h)}^{4}} & 6 {{(x_{n+1}+2h)}^{5}} & 7 {{(x_{n+1}+2h)}^{6}} & 8 {{(x_{n+1}+2h)}^{7}} & 9 {{(x_{n+1}+2h)}^{8}}\\
0 & 1 & 2 {(x_{n+1}+\frac{5}{2}h)} & 3 {{(x_{n+1}+\frac{5}{2}h)}^{2}} & 4 {{(x_{n+1}+\frac{5}{2}h)}^{3}} & 5 {{(x_{n+1}+\frac{5}{2}h)}^{4}} & 6 {{(x_{n+1}+\frac{5}{2}h)}^{5}} & 7 {{(x_{n+1}+\frac{5}{2}h)}^{6}} & 8 {{(x_{n+1}+\frac{5}{2}h)}^{7}} & 9 {{(x_{n+1}+\frac{5}{2}h)}^{8}}\\
0 & 1 & 2 {(x_{n+1}+3h)}& 3 {{(x_{n+1}+3h)}^{2}} & 4 {{(x_{n+1}+3h)}^{3}} & 5 {{(x_{n+1}+3h)}^{4}} & 6{{(x_{n+1}+3h)}^{5}} & 7 {{(x_{n+1}+3h)}^{6}} & 8 {{(x_{n+1}+3h)}^{7}} & 9 {{(x_{n+1}+3h)}^{8}}\\
0 & 1 & 2 {(x_{n+1}+\frac{7}{2}h)} & 3 {{(x_{n+1}+\frac{7}{2}h)}^{2}} & 4 {{(x_{n+1}+\frac{7}{2}h)}^{3}} & 5 {{(x_{n+1}+\frac{7}{2}h)}^{4}} & 6 {{(x_{n+1}+\frac{7}{2}h)}^{5}} & 7 {{(x_{n+1}+\frac{7}{2}h)}^{6}} & 8 {{(x_{n+1}+\frac{7}{2}h)}^{7}} & 9 {{(x_{n+1}+\frac{7}{2}h)}^{8}}
\end{bmatrix}
\end{equation}
The new Matrix is renamed B for ease of reference.\\
\par
The determinant of B is:
\[det (B) =\frac{15380234690625 {{h}^{36}}}{64}\]
The inverse of (\ref{mat}) is the C matrix calculated using \textbf{Maple} codes as shown in the \textbf{Appendix}.
Our only interest in the C matrix is it's first row and the elements are:
\begin{align*}
&c_{11}=1\\
&c_{12}=-\frac{160 {x_{n+1}^9}+2520 h {x_{n+1}^8}+16560 {h^2} {x_{n+1}^7}+58800 {h^3} {x_{n+1}^6}+121842 {h^4} {x_{n+1}^5}+147735 {h^5} {x_{n+1}^4}+98010 {h^6} {x_{n+1sing}^3}+28350 {h^7} {x_{n+1}^2}-473977 {h^9}}{2041200 {h^8}}\\
&c_{13}=\frac{320 {x_{n+1}^9}+4680 h {x_{n+1}^8}+27360 {h^2} {x_{n+1}^7}+78960 {h^3} {x_{n+1}^6}+102564 {h^4} {x_{n+1}^5}-9135 {h^5} {x_{n+1}^4}-197940 {h^6} {x_{n+1}^3}-237330 {h^7} {x_{n+1}^2}-113400 {h^8} {x_{n+1}}+343921 {h^9}}{113400 {h^8}}\\
&c_{14}=-\frac{1120 {x_{n+1}^9}+15750 h {x_{n+1}^8}+86760 {h^2} {x_{n+1}^7}+225750 {h^3} {x_{n+1}^6}+223524 {h^4} {x_{n+1}^5}-171675 {h^5} {x_{n+1}^4}-578340 {h^6} {x_{n+1}^3}-396900 {h^7} {x_{n+1}^2}+594011 {h^9}}{85050 {h^8}}\\
&c_{15}=\frac{560 {x_{n+1}^{9}}+7560 h {x_{n+1}^{8}}+39240 {{h}^{2}} {x_{n+1}^{7}}+92400 {{h}^{3}} {x_{n+1}^{6}}+68607 {{h}^{4}} {x_{n+1}^{5}}-101745 {{h}^{5}} {x_{ n+1}^{4}}-210735 {{h}^{6}} {x_{n+1}^{3}}-99225 {{h}^{7}} {x_{n+1}^{2}}+203338 {{h}^{9}}}{18900 {{h}^{8}}} \\
&c_{16}=-\frac{1120 {x_{n+1}^{9}}+14490 h {x_{n+1}^{8}}+70920 {{h}^{2}} {x_{n+1}^{7}}+152250 {{h}^{3}} {x_{n+1}^{6}}+84924 {{h}^{4}} {x_{n+1}^{5}}-191205 {{h}^{5}} {x_{n+1}^{4}}-310380 {{h}^{6}} {x_{n+1}^{3}}-132300 {{h}^{7}} {x_{n+1}^{2}}+310181 {{h}^{9}}}{28350 {{h}^{8}}}\\
&c_{17}=\frac{2240 {x_{n+1}^{9}}+27720 h {x_{n+1}^{8}}+128160 {{h}^{2}} {x_{n+1}^{7}}+253680 {{h}^{3}} {x_{n+1}^{6}}+109116 {{h}^{4}} {x_{n+1}^{5}}-336735 {{h}^{5}} {x_{n+1}^{4}}-487620 {{h}^{6}} {x_{n+1}^{3}}-198450 {{h}^{7}} {x_{n+1}^{2}}+501889 {{h}^{9}}}{68040 {{h}^{8}}}\\
&c_{18}=-\frac{160 {x_{n+1}^{9}}+1890 h {x_{n+1}^{8}}+8280 {{h}^{2}} {x_{n+1}^{7}}+15330 {{h}^{3}} {x_{n+1}^{6}}+5292 {{h}^{4}} {x_{n+1}^{5}}-21105 {{h}^{5}} {x_{n+1}^{4}}-28620 {{h}^{6}} {x_{n+1}^3}-11340 {{h}^{7}} {x_{n+1}^{2}}+30113 {{h}^{9}}}{9450 {h^8}}\\
&c_{19}=\frac{1120 {x_{n+1}^9}+12600 h {x_{n+1}^8}+52560 {h^2} {x_{n+1}^7}+92400 {h^3} {x_{n+1}^6}+26334 {h^4} {x_{n+1}^5}-130725 {h^5} {x_{n+1}^4}-169890 {h^6} {x_{n+1}^3}-66150 {h^7} {x_{n+1}^2}+181751 {h^9}}{226800 {h^8}}\\
&c_{(10)}=-\frac{160 {x_{n+1}^9}+1710 h {x_{n+1}^8}+6840 {h^2} {x_{n+1}^7}+11550 {h^3} {x_{n+1}^6}+2772 {h^4} {x_{n+1}^5}-16695 {h^5} {x_{n+1}^4}-21060 {h^6} {x_{n+1}^3}-8100 {h^7}{x_{n+1}^2}+22823 {h^9}}{255150{h^8}}
\end{align*}
From the above, we obtain the following continuous coefficients-This is obtained through Maple Codes as shown in the \textbf{Appendix}:
\begin{align*}
&\alpha_{0}(x)=y_{n}\\
&h\beta_{0}(x)=\frac{-160 {{w}^{9}}-2520 h {{w}^{8}}-16560 {{h}^{2}} {{w}^{7}}-58800 {{h}^{3}} {{w}^{6}}-121842 {{h}^{4}} {{w}^{5}}-147735 {{h}^{5}} {{w}^{4}}-98010 {{h}^{6}} {{w}^{3}}-28350 {{h}^{7}} {{w}^{2}}+473977 {{h}^{9}}}{2041200{h^8}}\\
&h\beta_{1}(x)=\frac{320 {{w}^{9}}+4680 h {{w}^{8}}+27360 {{h}^{2}} {{w}^{7}}+78960 {{h}^{3}} {{w}^{6}}+102564 {{h}^{4}} {{w}^{5}}-9135 {{h}^{5}} {{w}^{4}}-197940 {{h}^{6}} {{w}^{3}}-237330 {{h}^{7}} {{w}^{2}}-113400 {{h}^{8}} w+343921 {{h}^{9}}}{113400{h^8}}\\
&h\beta_{\frac{3}{2}}(x)=\frac{-1120 {{w}^{9}}-15750 h {{w}^{8}}-86760 {{h}^{2}} {{w}^{7}}-225750 {{h}^{3}} {{w}^{6}}-223524 {{h}^{4}} {{w}^{5}}+171675 {{h}^{5}} {{w}^{4}}+578340 {{h}^{6}} {{w}^{3}}+396900 {{h}^{7}} {{w}^{2}}-594011 {{h}^{9}}}{85050{h^8}}\\
&h\beta_{2}(x)=\frac{560 {{w}^{9}}+7560 h {{w}^{8}}+39240 {{h}^{2}} {{w}^{7}}+92400 {{h}^{3}} {{w}^{6}}+68607 {{h}^{4}} {{w}^{5}}-101745 {{h}^{5}} {{w}^{4}}-210735 {{h}^{6}} {{w}^{3}}-99225 {{h}^{7}} {{w}^{2}}+203338 {{h}^{9}}}{18900{h^8}}\\
&h\beta_{\frac{5}{2}}(x)=\frac{-1120 {w^9}-14490 h {w^8}-70920 {h^2} {w^7}-152250 {h^3} {w^6}-84924 {h^4} {w^5}+191205 {h^5} {w^4}+310380 {h^6} {w^3}+132300 {h^7} {w^2}-310181 {h^9}}{28350{h^8}}\\
&h\beta_{3}(x)=\frac{2240 {{w}^{9}}+27720 h {{w}^{8}}+128160 {{h}^{2}} {{w}^{7}}+253680 {{h}^{3}} {{w}^{6}}+109116 {{h}^{4}} {{w}^{5}}-336735 {{h}^{5}} {{w}^{4}}-487620 {{h}^{6}} {{w}^{3}}-198450 {{h}^{7}} {{w}^{2}}+501889 {{h}^{9}}}{68040{h^8}}\\
&h\beta_{\frac{7}{2}}(x)=\frac{-160 {{w}^{9}}-1890 h {{w}^{8}}-8280 {{h}^{2}} {{w}^{7}}-15330 {{h}^{3}} {{w}^{6}}-5292 {{h}^{4}} {{w}^{5}}+21105 {{h}^{5}} {{w}^{4}}+28620 {{h}^{6}} {{w}^{3}}+11340 {{h}^{7}} {{w}^{2}}-30113 {{h}^{9}}}{9450{h^8}}\\
&h\beta_{4}(x)=\frac{1120 {{w}^{9}}+12600 h {{w}^{8}}+52560 {{h}^{2}} {{w}^{7}}+92400 {{h}^{3}} {{w}^{6}}+26334 {{h}^{4}} {{w}^{5}}-130725 {{h}^{5}} {{w}^{4}}-169890 {{h}^{6}} {{w}^{3}}-66150 {{h}^{7}} {{w}^{2}}+181751 {{h}^{9}}}{226800{h^8}}\\
&h\beta_{\frac{9}{2}}(x)=\frac{-160 {{w}^{9}}-1710 h {{w}^{8}}-6840 {{h}^{2}} {{w}^{7}}-11550 {{h}^{3}} {{w}^{6}}-2772 {{h}^{4}} {{w}^{5}}+16695 {{h}^{5}} {{w}^{4}}+21060 {{h}^{6}} {{w}^{3}}+8100 {{h}^{7}} {{w}^{2}}-22823 {{h}^{9}}}{255150{h^8}}
\end{align*}
Evaluating the above at \[w=0, w=-\frac{h}{2}, w=-h, w=-\frac{3h}{2}, w=-2, w=-\frac{5h}{2}, w=-3, w=-\frac{7h}{2} \] to obtain the following discrete schemes:
\begin{align*}
&y_{n+1}=\frac{y_{n}}{2041200}+\frac{h}{2041200}\bigg[473977{f_n} +6190578f_{n+1}-14256264 f_{n+\frac{3}{2}}+21960504f_{n+2}-22333032f_{n+\frac{5}{2}}+15056670f_{ n+3}\\
&-6504408 f_{ n+\frac{7}{2}} +1635759 f_{ n+4}-182584 f_{n+\frac{9}{2}}\bigg]\\
&y_{n+\frac{3}{2}}=\frac{y_{n}}{89600}+\frac{h}{89600}\bigg[20759 {f_n} +287046 f_{ n+1} -581818 f_{ n+\frac{3}{2}}+936468 f_{ n+2}-958194 f_{ n+\frac{5}{2}} +647690 f_{ n+3} -280206f_{n+\frac{7}{2}} +70533 f_{ n+4}-7878 f_{ n+\frac{9}{2}}\bigg]\\
&y_{n+2}=\frac{y_{n}}{255150}+\frac{h}{255150}\bigg[59143{f_n}+814932f_{n+1}-1601616f_{\frac{n+3}{2}}+2762856f_{n+2}-2761488f_{\frac{n+5}{2}}+1860780f_{n+3}-803952f_{\frac{n+7}{2}}+202221f_{n+4}-22576f_{\frac{n+9}{2}}\bigg]\\
&y_{n+\frac{5}{2}}=\frac{y_{n}}{2612736}+\frac{h}{2612736}\bigg[605495{f_n}+8353350 f_{ n+1}-16467450 f_{ n+\frac{3}{2}}+28962900 f_{ n+2}-27460530-f_{ n+\frac{5}{2}}+18890250 f_{ n+3}8182350 f_{ n+\frac{7}{2}}\\
&+2060325f_{ n+4}-230150f_{ n+\frac{9}{2}}\bigg]\\
&y_{n+3}=\frac{y_{n}}{2800}+\frac{h}{2800}\bigg[649{f_n}+8946f_{n+1}-17608f_{n+\frac{3}{2}}+30888f_{n+2}-28584f_{n+\frac{5}{2}}+20990f_{n+3}-8856f_{n+\frac{7}{2}}+2223f_{n+4}-248f_{n+\frac{9}{2}}\bigg]\\
&y_{n+\frac{7}{2}}=\frac{y_{n}}{9331200}+\frac{h}{9331200}\bigg[2162377{f_n}+29837178f_{n+1}-58823814f_{n+\frac{3}{2}}+103389804f_{n+2}-96271182f_{n+\frac{5}{2}}+73295670f_{n+3}-27390258f_{n+\frac{7}{2}}\\&+7276059f_{n+4}-816634f_{n+\frac{9}{2}}\bigg]\\
&y_{n+4}=\frac{y_{n}}{127575}+\frac{h}{127575}\bigg[29578{f_n}+407232f_{n+1}-800256f_{n+\frac{3}{2}}+1402056f_{n+2}-1294848f_{n+\frac{5}{2}}+972480f_{n+3}-317952f_{n+\frac{7}{2}}+123786f_{n+4}-11776f_{n+\frac{9}{2}}\bigg]\\
&y_{n+\frac{9}{2}}=\frac{y_{n}}{89600}+\frac{h}{89600}\bigg[20727{f_n}+288198f_{n+1}-574074f_{n+\frac{3}{2}}+1017684f_{n+2}-965682f_{n+\frac{5}{2}}+748170f_{n+3}-278478f_{n+\frac{7}{2}}+141669f_{n+4}4986f_{n+\frac{9}{2}}\bigg]
\end{align*}
\end{document}
I initially did this work in landscape, but I need it in portrait. I am at wits end and in a time crunch. Below is the work I initially did using landscape mode
\documentclass[a4paper,12pt,landscape]{book}
\usepackage[inner=1.3cm, outer=1.3cm, top=2cm, bottom=2cm, bindingoffset=1cm]{geometry}
\usepackage[utf8]{inputenc}
\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{mathtools}
\begin{document}
\title{Chapter 3}
\author{Akor Eleojo Rachel}
\maketitle
Consider the Linear Multi-step Method:
\begin{equation}
\begin{split}
y(x) =& \alpha_{0}(x)y_{n} + h\bigg[\beta_{0}(x)f_{n}+\beta_{1}(x)f_{n+1}+\beta_{\frac{3}{2}}(x)f_{n+\frac{3}{2}}+\beta_{2}(x)f_{n+2}+\beta_{\frac{5}{2}}(x)f_{n+\frac{5}{2}}+\beta_{3}(x)f_{n+3}+\beta_{\frac{7}{2}}(x)f_{n+\frac{7}{2}} \\ =\ &+\beta_{4}(x)f_{n+4}+\beta_{\frac{9}{2}}(x)f_{n+\frac{9}{2}}\bigg]
\end{split}
\end{equation}
\begin{equation}
A=\begin{bmatrix}
1 & {x_n} & {{x_n}^{2}} & {{x_n}^{3}} & {{x_n}^{4}} & {{x_n}^{5}} & {{x_n}^{6}} & {{x_n}^{7}} & {{x_n}^{8}} & {{x_n}^{9}}\\
0 & 1 & 2 {x_n} & 3 {{x_n}^{2}} & 4 {{x_n}^{3}} & 5 {{x_n}^{4}} & 6 {{x_n}^{5}} & 7 {{x_n}^{6}} & 8 {{x_n}^{7}} & 9 {{x_n}^{8}}\\
0 & 1 & 2 {x_{n+1}} & 3 {{x_{n+1}}^{2}} & 4 {{x_{n+1}}^{3}} & 5 {{x_{n+1}}^{4}} & 6{{x_{n+1}}^{5}} & 7 {{x_{n+1}}^{6}} & 8 {{x_{ n+1}}^{7}} & 9 {{x_{n+1}}^{8}}\\
0 & 1 & 2 {x_{n+\frac{3}{2}}} & 3 {{x_{n+\frac{3}{2}}}^{2}}& 4 {{x_{n+\frac{3}{2}}}^{3}} & 5 {{x_{n+\frac{3}{2}}}^{4}} & 6 {{x_{n+\frac{3}{2}}}^{5}} & 7 {{x_{n+\frac{3}{2}}}^{6}} & 8 {{x_{n+\frac{3}{2}}}^{7}} & 9 {{x_{n+\frac{3}{2}}}^{8}}\\
0 & 1 & 2 {x_{n+2}}& 3 {{x_{n+2}}^{2}} & 4 {{x_{n+2}}^{3}} & 5 {{x_{n+2}}^{4}} & 6 {{x_{ n+2}}^{5}} & 7 {{x_{n+2}}^{6}} & 8 {{x_{n+2}}^{7}} & 9 {{x_{n+2}}^{8}}\\
0 & 1 & 2 {x_{n+\frac{5}{2}}} & 3 {{x_{n+\frac{5}{2}}}^{2}} & 4 {{x_{n+\frac{5}{2}}}^{3}} & 5{{x_{n+\frac{5}{2}}}^{4}} & 6 {{x_{n+\frac{5}{2}}}^{5}} & 7 {{x_{n+\frac{5}{2}}}^{6}} & 8 {{x_{n+\frac{5}{2}}}^{7}} & 9 {{x_{n+\frac{5}{2}}}^{8}}\\
0 & 1 & 2 {x_{n+3}} & 3 {{x_{n+3}}^{2}} & 4 {{x_{n+3}}^{3}} & 5 {{x_{n+3}}^{4}} & 6 {{x_{ n+3} }^{5}} & 7 {{x_{n+3}}^{6}} & 8 {{x_{n+3}}^{7}} & 9 {{x_{n+3}}^{8}}\\
0 & 1 & 2 {x_{n+\frac{7}{2}}} & 3 {{x_{n+\frac{7}{2}}}^{2}} & 4 {{x_{n+\frac{7}{2}}}^{3}} & 5 {{x_{n+\frac{7}{2}}}^{4}} & 6 {{x_{n+\frac{7}{2}}}^{5}} & 7 {{x_{n+\frac{7}{2}}}^{6}} & 8 {{x_{n+\frac{7}{2}}}^{7}} & 9 {{x_{n+\frac{7}{2}}}^{8}}\\
0 & 1 & 2 {x_{n+4}}& 3 {{x_{n+4}}^{2}} & 4 {{x_{n+4}}^{3}} & 5 {{x_{n+4}}^{4}} & 6{{x_{ n+4} }^{5}} & 7 {{x_{n+4}}^{6}} & 8 {{x_{n+4}}^{7}} & 9 {{x_{n+4}}^{8}}\\
0 & 1 & 2 {x_{n+\frac{9}{2}}} & 3 {{x_{n+\frac{9}{2}}}^{2}} & 4 {{x_{n+\frac{9}{2}}}^{3}} & 5 {{x_{ n+\frac{9}{2}}}^{4}} & 6 {{x_{n+\frac{9}{2}}}^{5}} & 7 {{x_{n+\frac{9}{2}}}^{6}} & 8 {{x_{n+\frac{9}{2}}}^{7}} & 9 {{x_{n+\frac{9}{2}}}^{8}}
\end{bmatrix}
\end{equation}
Replacing: {\large$x_{n}, x_{n+\frac{3}{2}}, x_{n+2}, x_{n+\frac{5}{2}}, x_{n+3}, x_{n+\frac{7}{2}}, x_{n+4}, x_{n+\frac{9}{2}}$}\\
with: $x_{n+1}-h, x_{n+1}+\frac{1}{2}h, x_{n+1}+h, x_{n+1}+\frac{3}{2}h, x_{n+1}+2h, x_{n+1}+\frac{5}{2}h, x_{n+1}+3h, x_{n+1}+\frac{7}{2}h$\\
we obtain:
\begin{equation}
\label{mat}
B=\begin{bmatrix}
1 & {x_{n+1}-h} & {{(x_{n+1}-h)}^{2}} & {{(x_{n+1}-h)}^{3}} & {{(x_{n+1}-h)}^{4}} & {{(x_{n+1}-h)}^{5}} & {{(x_{n+1}-h)}^{6}} & {{(x_{n+1}-h)}^{7}} & {{(x_{n+1}-h)}^{8}} & {{(x_{n+1}-h)}^{9}}\\
0 & 1 & 2 {(x_{n+1}-h)} & 3 {{(x_{n+1}-h)}^{2}} & 4 {{(x_{n+1}-h)}^{3}} & 5 {{(x_{n+1}-h)}^{4}} & 6 {{(x_{n+1}-h)}^{5}} & 7 {{(x_{n+1}-h)}^{6}} & 8 {{(x_{n+1}-h)}^{7}} & 9 {{(x_{n+1}-h)}^{8}}\\
0 & 1 & 2 {x_{n+1}} & 3 {{x_{n+1}}^{2}} & 4 {{x_{n+1}}^{3}} & 5 {{x_{n+1}}^{4}} & 6{{x_{n+1}}^{5}} & 7 {{x_{n+1}}^{6}} & 8 {{x_{ n+1}}^{7}} & 9 {{x_{n+1}}^{8}}\\
0 & 1 & 2 {(x_{n+1}+\frac{1}{2}h)} & 3 {{(x_{n+1}+\frac{1}{2}h)}^{2}}& 4 {{(x_{n+1}+\frac{1}{2}h)}^{3}} & 5 {{(x_{n+1}+\frac{1}{2}h)}^{4}} & 6 {{(x_{n+1}+\frac{1}{2}h)}^{5}} & 7 {{(x_{n+1}+\frac{1}{2}h)}^{6}} & 8 {{(x_{n+1}+\frac{1}{2}h)}^{7}} & 9 {{(x_{n+1}+\frac{1}{2}h)}^{8}}\\
0 & 1 & 2 {(x_{n+1}+h)}& 3 {{(x_{n+1}+h)}^{2}} & 4 {{(x_{n+1}+h)}^{3}} & 5 {{(x_{n+1}+h)}^{4}} & 6 {{(x_{n+1}+h)}^{5}} & 7 {{(x_{n+1}+h)}^{6}} & 8 {{(x_{n+1}+h)}^{7}} & 9 {{(x_{n+1}+h)}^{8}}\\
0 & 1 & 2 {(x_{n+1}+\frac{3}{2}h)} & 3 {{(x_{n+1}+\frac{3}{2}h)}^{2}} & 4 {{(x_{n+1}+\frac{3}{2}h)}^{3}} & 5{{(x_{n+1}+\frac{3}{2}h)}^{4}} & 6 {{(x_{n+1}+\frac{3}{2}h)}^{5}} & 7 {{(x_{n+1}+\frac{3}{2}h)}^{6}} & 8 {{(x_{n+1}+\frac{3}{2}h)}^{7}} & 9 {{(x_{n+1}+\frac{3}{2}h)}^{8}}\\
0 & 1 & 2 {(x_{n+1}+2h)} & 3 {{(x_{n+1}+2h)}^{2}} & 4 {{(x_{n+1}+2h)}^{3}} & 5 {{(x_{n+1}+2h)}^{4}} & 6 {{(x_{n+1}+2h)}^{5}} & 7 {{(x_{n+1}+2h)}^{6}} & 8 {{(x_{n+1}+2h)}^{7}} & 9 {{(x_{n+1}+2h)}^{8}}\\
0 & 1 & 2 {(x_{n+1}+\frac{5}{2}h)} & 3 {{(x_{n+1}+\frac{5}{2}h)}^{2}} & 4 {{(x_{n+1}+\frac{5}{2}h)}^{3}} & 5 {{(x_{n+1}+\frac{5}{2}h)}^{4}} & 6 {{(x_{n+1}+\frac{5}{2}h)}^{5}} & 7 {{(x_{n+1}+\frac{5}{2}h)}^{6}} & 8 {{(x_{n+1}+\frac{5}{2}h)}^{7}} & 9 {{(x_{n+1}+\frac{5}{2}h)}^{8}}\\
0 & 1 & 2 {(x_{n+1}+3h)}& 3 {{(x_{n+1}+3h)}^{2}} & 4 {{(x_{n+1}+3h)}^{3}} & 5 {{(x_{n+1}+3h)}^{4}} & 6{{(x_{n+1}+3h)}^{5}} & 7 {{(x_{n+1}+3h)}^{6}} & 8 {{(x_{n+1}+3h)}^{7}} & 9 {{(x_{n+1}+3h)}^{8}}\\
0 & 1 & 2 {(x_{n+1}+\frac{7}{2}h)} & 3 {{(x_{n+1}+\frac{7}{2}h)}^{2}} & 4 {{(x_{n+1}+\frac{7}{2}h)}^{3}} & 5 {{(x_{n+1}+\frac{7}{2}h)}^{4}} & 6 {{(x_{n+1}+\frac{7}{2}h)}^{5}} & 7 {{(x_{n+1}+\frac{7}{2}h)}^{6}} & 8 {{(x_{n+1}+\frac{7}{2}h)}^{7}} & 9 {{(x_{n+1}+\frac{7}{2}h)}^{8}}
\end{bmatrix}
\end{equation}
The new Matrix is renamed B for ease of reference.\\
\par
The determinant of B is:
\[det (B) =\frac{15380234690625 {{h}^{36}}}{64}\]
The inverse of (\ref{mat}) is the C matrix calculated using \textbf{Maple} codes as shown in the \textbf{Appendix}.
Our only interest in the C matrix is it's first row and the elements are:
\begin{align*}
&c_{11}=1\\
&c_{12}=-\frac{160 {x_{n+1}^9}+2520 h {x_{n+1}^8}+16560 {h^2} {x_{n+1}^7}+58800 {h^3} {x_{n+1}^6}+121842 {h^4} {x_{n+1}^5}+147735 {h^5} {x_{n+1}^4}+98010 {h^6} {x_{n+1sing}^3}+28350 {h^7} {x_{n+1}^2}-473977 {h^9}}{2041200 {h^8}}\\
&c_{13}=\frac{320 {x_{n+1}^9}+4680 h {x_{n+1}^8}+27360 {h^2} {x_{n+1}^7}+78960 {h^3} {x_{n+1}^6}+102564 {h^4} {x_{n+1}^5}-9135 {h^5} {x_{n+1}^4}-197940 {h^6} {x_{n+1}^3}-237330 {h^7} {x_{n+1}^2}-113400 {h^8} {x_{n+1}}+343921 {h^9}}{113400 {h^8}}\\
&c_{14}=-\frac{1120 {x_{n+1}^9}+15750 h {x_{n+1}^8}+86760 {h^2} {x_{n+1}^7}+225750 {h^3} {x_{n+1}^6}+223524 {h^4} {x_{n+1}^5}-171675 {h^5} {x_{n+1}^4}-578340 {h^6} {x_{n+1}^3}-396900 {h^7} {x_{n+1}^2}+594011 {h^9}}{85050 {h^8}}\\
&c_{15}=\frac{560 {x_{n+1}^{9}}+7560 h {x_{n+1}^{8}}+39240 {{h}^{2}} {x_{n+1}^{7}}+92400 {{h}^{3}} {x_{n+1}^{6}}+68607 {{h}^{4}} {x_{n+1}^{5}}-101745 {{h}^{5}} {x_{ n+1}^{4}}-210735 {{h}^{6}} {x_{n+1}^{3}}-99225 {{h}^{7}} {x_{n+1}^{2}}+203338 {{h}^{9}}}{18900 {{h}^{8}}} \\
&c_{16}=-\frac{1120 {x_{n+1}^{9}}+14490 h {x_{n+1}^{8}}+70920 {{h}^{2}} {x_{n+1}^{7}}+152250 {{h}^{3}} {x_{n+1}^{6}}+84924 {{h}^{4}} {x_{n+1}^{5}}-191205 {{h}^{5}} {x_{n+1}^{4}}-310380 {{h}^{6}} {x_{n+1}^{3}}-132300 {{h}^{7}} {x_{n+1}^{2}}+310181 {{h}^{9}}}{28350 {{h}^{8}}}\\
&c_{17}=\frac{2240 {x_{n+1}^{9}}+27720 h {x_{n+1}^{8}}+128160 {{h}^{2}} {x_{n+1}^{7}}+253680 {{h}^{3}} {x_{n+1}^{6}}+109116 {{h}^{4}} {x_{n+1}^{5}}-336735 {{h}^{5}} {x_{n+1}^{4}}-487620 {{h}^{6}} {x_{n+1}^{3}}-198450 {{h}^{7}} {x_{n+1}^{2}}+501889 {{h}^{9}}}{68040 {{h}^{8}}}\\
&c_{18}=-\frac{160 {x_{n+1}^{9}}+1890 h {x_{n+1}^{8}}+8280 {{h}^{2}} {x_{n+1}^{7}}+15330 {{h}^{3}} {x_{n+1}^{6}}+5292 {{h}^{4}} {x_{n+1}^{5}}-21105 {{h}^{5}} {x_{n+1}^{4}}-28620 {{h}^{6}} {x_{n+1}^3}-11340 {{h}^{7}} {x_{n+1}^{2}}+30113 {{h}^{9}}}{9450 {h^8}}\\
&c_{19}=\frac{1120 {x_{n+1}^9}+12600 h {x_{n+1}^8}+52560 {h^2} {x_{n+1}^7}+92400 {h^3} {x_{n+1}^6}+26334 {h^4} {x_{n+1}^5}-130725 {h^5} {x_{n+1}^4}-169890 {h^6} {x_{n+1}^3}-66150 {h^7} {x_{n+1}^2}+181751 {h^9}}{226800 {h^8}}\\
&c_{(10)}=-\frac{160 {x_{n+1}^9}+1710 h {x_{n+1}^8}+6840 {h^2} {x_{n+1}^7}+11550 {h^3} {x_{n+1}^6}+2772 {h^4} {x_{n+1}^5}-16695 {h^5} {x_{n+1}^4}-21060 {h^6} {x_{n+1}^3}-8100 {h^7}{x_{n+1}^2}+22823 {h^9}}{255150{h^8}}
\end{align*}
From the above, we obtain the following continuous coefficients-This is obtained through Maple Codes as shown in the \textbf{Appendix}:
\begin{align*}
&\alpha_{0}(x)=y_{n}\\
&h\beta_{0}(x)=\frac{-160 {{w}^{9}}-2520 h {{w}^{8}}-16560 {{h}^{2}} {{w}^{7}}-58800 {{h}^{3}} {{w}^{6}}-121842 {{h}^{4}} {{w}^{5}}-147735 {{h}^{5}} {{w}^{4}}-98010 {{h}^{6}} {{w}^{3}}-28350 {{h}^{7}} {{w}^{2}}+473977 {{h}^{9}}}{2041200{h^8}}\\
&h\beta_{1}(x)=\frac{320 {{w}^{9}}+4680 h {{w}^{8}}+27360 {{h}^{2}} {{w}^{7}}+78960 {{h}^{3}} {{w}^{6}}+102564 {{h}^{4}} {{w}^{5}}-9135 {{h}^{5}} {{w}^{4}}-197940 {{h}^{6}} {{w}^{3}}-237330 {{h}^{7}} {{w}^{2}}-113400 {{h}^{8}} w+343921 {{h}^{9}}}{113400{h^8}}\\
&h\beta_{\frac{3}{2}}(x)=\frac{-1120 {{w}^{9}}-15750 h {{w}^{8}}-86760 {{h}^{2}} {{w}^{7}}-225750 {{h}^{3}} {{w}^{6}}-223524 {{h}^{4}} {{w}^{5}}+171675 {{h}^{5}} {{w}^{4}}+578340 {{h}^{6}} {{w}^{3}}+396900 {{h}^{7}} {{w}^{2}}-594011 {{h}^{9}}}{85050{h^8}}\\
&h\beta_{2}(x)=\frac{560 {{w}^{9}}+7560 h {{w}^{8}}+39240 {{h}^{2}} {{w}^{7}}+92400 {{h}^{3}} {{w}^{6}}+68607 {{h}^{4}} {{w}^{5}}-101745 {{h}^{5}} {{w}^{4}}-210735 {{h}^{6}} {{w}^{3}}-99225 {{h}^{7}} {{w}^{2}}+203338 {{h}^{9}}}{18900{h^8}}\\
&h\beta_{\frac{5}{2}}(x)=\frac{-1120 {w^9}-14490 h {w^8}-70920 {h^2} {w^7}-152250 {h^3} {w^6}-84924 {h^4} {w^5}+191205 {h^5} {w^4}+310380 {h^6} {w^3}+132300 {h^7} {w^2}-310181 {h^9}}{28350{h^8}}\\
&h\beta_{3}(x)=\frac{2240 {{w}^{9}}+27720 h {{w}^{8}}+128160 {{h}^{2}} {{w}^{7}}+253680 {{h}^{3}} {{w}^{6}}+109116 {{h}^{4}} {{w}^{5}}-336735 {{h}^{5}} {{w}^{4}}-487620 {{h}^{6}} {{w}^{3}}-198450 {{h}^{7}} {{w}^{2}}+501889 {{h}^{9}}}{68040{h^8}}\\
&h\beta_{\frac{7}{2}}(x)=\frac{-160 {{w}^{9}}-1890 h {{w}^{8}}-8280 {{h}^{2}} {{w}^{7}}-15330 {{h}^{3}} {{w}^{6}}-5292 {{h}^{4}} {{w}^{5}}+21105 {{h}^{5}} {{w}^{4}}+28620 {{h}^{6}} {{w}^{3}}+11340 {{h}^{7}} {{w}^{2}}-30113 {{h}^{9}}}{9450{h^8}}\\
&h\beta_{4}(x)=\frac{1120 {{w}^{9}}+12600 h {{w}^{8}}+52560 {{h}^{2}} {{w}^{7}}+92400 {{h}^{3}} {{w}^{6}}+26334 {{h}^{4}} {{w}^{5}}-130725 {{h}^{5}} {{w}^{4}}-169890 {{h}^{6}} {{w}^{3}}-66150 {{h}^{7}} {{w}^{2}}+181751 {{h}^{9}}}{226800{h^8}}\\
&h\beta_{\frac{9}{2}}(x)=\frac{-160 {{w}^{9}}-1710 h {{w}^{8}}-6840 {{h}^{2}} {{w}^{7}}-11550 {{h}^{3}} {{w}^{6}}-2772 {{h}^{4}} {{w}^{5}}+16695 {{h}^{5}} {{w}^{4}}+21060 {{h}^{6}} {{w}^{3}}+8100 {{h}^{7}} {{w}^{2}}-22823 {{h}^{9}}}{255150{h^8}}
\end{align*}
Evaluating the above at \[w=0, w=-\frac{h}{2}, w=-h, w=-\frac{3h}{2}, w=-2, w=-\frac{5h}{2}, w=-3, w=-\frac{7h}{2} \] to obtain the following discrete schemes:
\begin{align*}
&y_{n+1}=\frac{y_{n}}{2041200}+\frac{h}{2041200}\bigg[473977{f_n} +6190578f_{n+1}-14256264 f_{n+\frac{3}{2}}+21960504f_{n+2}-22333032f_{n+\frac{5}{2}}+15056670f_{ n+3}\\
&-6504408 f_{ n+\frac{7}{2}} +1635759 f_{ n+4}-182584 f_{n+\frac{9}{2}}\bigg]\\
&y_{n+\frac{3}{2}}=\frac{y_{n}}{89600}+\frac{h}{89600}\bigg[20759 {f_n} +287046 f_{ n+1} -581818 f_{ n+\frac{3}{2}}+936468 f_{ n+2}-958194 f_{ n+\frac{5}{2}} +647690 f_{ n+3} -280206f_{n+\frac{7}{2}} +70533 f_{ n+4}-7878 f_{ n+\frac{9}{2}}\bigg]\\
&y_{n+2}=\frac{y_{n}}{255150}+\frac{h}{255150}\bigg[59143{f_n}+814932f_{n+1}-1601616f_{\frac{n+3}{2}}+2762856f_{n+2}-2761488f_{\frac{n+5}{2}}+1860780f_{n+3}-803952f_{\frac{n+7}{2}}+202221f_{n+4}-22576f_{\frac{n+9}{2}}\bigg]\\
&y_{n+\frac{5}{2}}=\frac{y_{n}}{2612736}+\frac{h}{2612736}\bigg[605495{f_n}+8353350 f_{ n+1}-16467450 f_{ n+\frac{3}{2}}+28962900 f_{ n+2}-27460530-f_{ n+\frac{5}{2}}+18890250 f_{ n+3}8182350 f_{ n+\frac{7}{2}}\\
&+2060325f_{ n+4}-230150f_{ n+\frac{9}{2}}\bigg]\\
&y_{n+3}=\frac{y_{n}}{2800}+\frac{h}{2800}\bigg[649{f_n}+8946f_{n+1}-17608f_{n+\frac{3}{2}}+30888f_{n+2}-28584f_{n+\frac{5}{2}}+20990f_{n+3}-8856f_{n+\frac{7}{2}}+2223f_{n+4}-248f_{n+\frac{9}{2}}\bigg]\\
&y_{n+\frac{7}{2}}=\frac{y_{n}}{9331200}+\frac{h}{9331200}\bigg[2162377{f_n}+29837178f_{n+1}-58823814f_{n+\frac{3}{2}}+103389804f_{n+2}-96271182f_{n+\frac{5}{2}}+73295670f_{n+3}-27390258f_{n+\frac{7}{2}}\\&+7276059f_{n+4}-816634f_{n+\frac{9}{2}}\bigg]\\
&y_{n+4}=\frac{y_{n}}{127575}+\frac{h}{127575}\bigg[29578{f_n}+407232f_{n+1}-800256f_{n+\frac{3}{2}}+1402056f_{n+2}-1294848f_{n+\frac{5}{2}}+972480f_{n+3}-317952f_{n+\frac{7}{2}}+123786f_{n+4}-11776f_{n+\frac{9}{2}}\bigg]\\
&y_{n+\frac{9}{2}}=\frac{y_{n}}{89600}+\frac{h}{89600}\bigg[20727{f_n}+288198f_{n+1}-574074f_{n+\frac{3}{2}}+1017684f_{n+2}-965682f_{n+\frac{5}{2}}+748170f_{n+3}-278478f_{n+\frac{7}{2}}+141669f_{n+4}4986f_{n+\frac{9}{2}}\bigg]
\end{align*}
\end{document}
mathtools
loadsamsmath
andamssymb
loadsamsfonts
, so the preamble can be cleaned up a bit.