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      <text>7.2.4.3 3x3 identity and zero matrix</text>
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      <text><![CDATA[<p>The \(3\times 3\) unit matrix is: \[ I = \begin{bmatrix} 1 &amp; 0 &amp; 0 \\ 0 &amp; 1 &amp; 0 \\ 0 &amp; 0 &amp; 1 \end{bmatrix} \]  and as in the \(2\times 2\) case this has the property that \( AI = IA = A \) for all matrices \(A\).<br></p>
<p>The \(3\times 3\) zero matrix is \[ \underline{0} = \begin{bmatrix} 0 &amp; 0 &amp; 0 \\ 0 &amp; 0 &amp; 0 \\ 0 &amp; 0 &amp; 0 \end{bmatrix} \]</p>]]></text>
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