<exercise>
<statement>
Let <m>T:\mathbb{R}^<xsl:value-of select="columns"/> \to \mathbb{R}^<xsl:value-of select="rows"/></m> be the linear transformation given by the standard matrix
<m><xsl:value-of select="matrix"/>.</m>
<ol>
<li>Explain why <m>T</m> is or is not injective.</li>
<li>Explain why <m>T</m> is or is not surjective.</li>
</ol>
</statement>
<answer>
<p><me>\operatorname{RREF}<xsl:value-of select="matrix"/>=<xsl:value-of select="rref"/></me></p>
<ol>
<li>
<xsl:choose>
<xsl:when test="injective"> <m>T</m> is injective.</xsl:when>
<xsl:otherwise> <m>T</m> is not injective</xsl:otherwise>
</xsl:choose>
</li>
<li>
<xsl:choose>
<xsl:when test="surjective"> <m>T</m> is surjective.</xsl:when>
<xsl:otherwise> <m>T</m> is not surjective</xsl:otherwise>
</xsl:choose>
</li>
</ol>
</answer>
</exercise>