From e1af33e8058391100082b26555639f72ba538baf Mon Sep 17 00:00:00 2001 From: Joshua Potter Date: Sat, 13 May 2023 07:14:03 -0600 Subject: [PATCH] Have definitions at top in "glossary" chapter. --- Bookshelf/Apostol.tex | 93 ++++++++++++++++++++++--------------------- 1 file changed, 47 insertions(+), 46 deletions(-) diff --git a/Bookshelf/Apostol.tex b/Bookshelf/Apostol.tex index eaf3b47..1afecaf 100644 --- a/Bookshelf/Apostol.tex +++ b/Bookshelf/Apostol.tex @@ -17,6 +17,53 @@ \tableofcontents +\chapter{Glossary}% +\label{chap:glossary} + +\section{\defined{Partition}}% +\label{sec:def-partition} + +Let $[a, b]$ be a closed interval decomposed into $n$ subintervals by inserting + $n - 1$ points of subdivision, say $x_1$, $x_2$, $\ldots$, $x_{n-1}$, subject + only to the restriction + \begin{equation} + \label{sec:partition-eq1} + a < x_1 < x_2 < \cdots < x_{n-1} < b. + \end{equation} +It is convenient to denote the point $a$ itself by $x_0$ and the point $b$ by + $x_n$. +A collection of points satisfying \eqref{sec:partition-eq1} is called a + \textbf{partition} $P$ of $[a, b]$, and we use the symbol + $$P = \{x_0, x_1, \ldots, x_n\}$$ to designate this partition. + +\begin{definition} + + \lean{Common/Set/Intervals/Partition}{Set.Intervals.Partition} + +\end{definition} + +\section{\defined{Step Function}}% +\label{sec:def-step-function} + +A function $s$, whose domain is a closed interval $[a, b]$, is called a step + function if there is a \nameref{sec:def-partition} + $P = \{x_0, x_1, \ldots, x_n\}$ of $[a b]$ such that $s$ is constant on each + open subinterval of $P$. +That is to say, for each $k = 1, 2, \ldots, n$, there is a real number $s_k$ + such that $$s(x) = s_k \quad\text{if}\quad x_{k-1} < x < x_k.$$ +Step functions are sometimes called piecewise constant functions. + +\vspace{8pt} +\noindent +\textit{Note:} At each of the endpoints $x_{k-1}$ and $x_k$ the function must + have some well-defined value, but this need not be the same as $s_k$. + +\begin{definition} + + \lean{Common/Set/Intervals/StepFunction}{Set.Intervals.StepFunction} + +\end{definition} + \chapter{A Set of Axioms for the Real-Number System}% \label{chap:set-axioms-real-number-system} @@ -1085,52 +1132,6 @@ Prove that the set function $n$ satisfies the first three axioms for area. \end{proof} -\chapter{Partitions and Step Functions}% -\label{chap:partitions-step-functions} - -\section{\defined{Partition}}% -\label{sec:partition} - -Let $[a, b]$ be a closed interval decomposed into $n$ subintervals by inserting - $n - 1$ points of subdivision, say $x_1$, $x_2$, $\ldots$, $x_{n-1}$, subject - only to the restriction - \begin{equation} - \label{sec:partition-eq1} - a < x_1 < x_2 < \cdots < x_{n-1} < b. - \end{equation} -It is convenient to denote the point $a$ itself by $x_0$ and the point $b$ by - $x_n$. -A collection of points satisfying \eqref{sec:partition-eq1} is called a - \textbf{partition} $P$ of $[a, b]$, and we use the symbol - $$P = \{x_0, x_1, \ldots, x_n\}$$ to designate this partition. - -\begin{definition} - - \lean{Common/Set/Intervals/Partition}{Set.Intervals.Partition} - -\end{definition} - -\section{\defined{Step Function}}% -\label{sec:step-function} - -A function $s$, whose domain is a closed interval $[a, b]$, is called a step - function if there is a \nameref{sec:partition} $P = \{x_0, x_1, \ldots, x_n\}$ - of $[a b]$ such that $s$ is constant on each open subinterval of $P$. -That is to say, for each $k = 1, 2, \ldots, n$, there is a real number $s_k$ - such that $$s(x) = s_k \quad\text{if}\quad x_{k-1} < x < x_k.$$ -Step functions are sometimes called piecewise constant functions. - -\vspace{8pt} -\noindent -\textit{Note:} At each of the endpoints $x_{k-1}$ and $x_k$ the function must - have some well-defined value, but this need not be the same as $s_k$. - -\begin{definition} - - \lean{Common/Set/Intervals/StepFunction}{Set.Intervals.StepFunction} - -\end{definition} - \chapter{Exercises 1.11}% \label{chap:exercises-1-11}