\chapter{Polynomial and rational functions} \section{The Rational Zero Theorem}
Check your understanding
Answer the questions in your own words. \begin{enumerate} \item Numbers such as \(1,-2,0,-3,8\) are called \textit{integers}. What are numbers such as \(1/2, -3/5, 3/7\) called? \item What are numbers such as \(\sqrt{2}\), \(\pi\), \(\pi^2/3\) called? \item The polynomial \(x^2-7\) cannot be factored using integers. Does that mean that it cannot be be factored at all? \item Neither \(x^2-7\) nor \(x^2+7\) can be factored using integers. But what is the difference between the two cases? \item What is a rational zero of a polynomial \(f(x)\)? \item What does the Rational Zero Theorem say? \item Suppose the degree of \(f(x)\) is \(3\) and its possible rational zeros are \(\pm 1, \pm 4, \pm 7\). After trying synthetic division with \(x=1\) and \(x=-1\) without success, we find that \(x=4\) works. What is our next step? \item Suppose now that \(f(x)\) has degree \(4\) and the list of possible rational zeros is \(\pm 1, \pm 2, \pm 3, \pm 6\). After trying \(x=1\), \(x=-1\), \(x=2\) without success, we find that \(x=-2\) works. What is our next step? \end{enumerate}
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