<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Matrix Theory on Chen Kai Blog</title><link>https://www.chenk.top/en/tags/matrix-theory/</link><description>Recent content in Matrix Theory on Chen Kai Blog</description><generator>Hugo</generator><language>en</language><lastBuildDate>Wed, 21 Jan 2026 09:00:00 +0000</lastBuildDate><atom:link href="https://www.chenk.top/en/tags/matrix-theory/index.xml" rel="self" type="application/rss+xml"/><item><title>ML Math Derivations (2): Linear Algebra and Matrix Theory</title><link>https://www.chenk.top/en/ml-math-derivations/02-linear-algebra-and-matrix-theory/</link><pubDate>Wed, 21 Jan 2026 09:00:00 +0000</pubDate><guid>https://www.chenk.top/en/ml-math-derivations/02-linear-algebra-and-matrix-theory/</guid><description>&lt;p>&lt;figure class="article-figure">
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&lt;h2 id="why-this-chapter-and-whats-different" class="heading-anchor">Why this chapter, and what&amp;rsquo;s different&lt;a href="#why-this-chapter-and-whats-different" class="heading-link" aria-label="Permalink to this section" title="Copy link to this section">#&lt;/a>
&lt;/h2>&lt;p>If you have already worked through a standard linear-algebra course you have seen most of these objects. &lt;strong>This chapter is not that course.&lt;/strong> It is the &lt;em>ML practitioner&amp;rsquo;s slice&lt;/em> of linear algebra: the half-dozen ideas that actually appear when you implement gradient descent, run PCA, train a neural net, or read a paper.&lt;/p></description></item></channel></rss>