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<p>We often want to find the line (or plane, or hyperplane) that best fits our data. This amounts to finding the best possible approximation to some unsolvable system of linear equations <em>A</em>x = b. The algebra of finding these best fit solutions begins with the projection of a vector onto a subspace.</p>
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<p><a href="/assets/courseware/v1/3ed2593743bcbca45941fa12d4473074/asset-v1:OCW+18.06SC+2T2019+type@asset+block/18.06_Unit_II_2.2_Lectrans.pdf" target="[object Object]">Lecture video transcript (PDF)</a></p>
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<h2 class="hd hd-2 unit-title">Lecture Summary and Reading</h2>
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<h3>Lecture Summary</h3>
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<li><a href="/assets/courseware/v1/fe6c9742b95701187e423306f7248d70/asset-v1:OCW+18.06SC+2T2019+type@asset+block/18.06_Unit_II_2.2_Lecsum.pdf" target="[object Object]">Projections onto Subspaces (PDF)</a></li>
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<h3>Suggested Reading</h3>
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<li>Read Section 4.2 in the 4<sup>th</sup> or 5<sup>th</sup> edition.</li>
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<h3 class="hd hd-2">Projections onto Subspaces</h3>
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<p>Work the problems on your own and check your answers when you're done.</p>
<p><a href="/assets/courseware/v1/d905f0ca49bad78c0a47f079a5edc5a5/asset-v1:OCW+18.06SC+2T2019+type@asset+block/18.06_Unit_II_2.2_Exercises.pdf" target="[object Object]">Exercises on projections onto subspaces (PDF)</a></p>
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