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<h2 class="hd hd-2 unit-title">1.5 Session Overview</h2>
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<p>This session explains inverses, transposes and permutation matrices. We also learn how elimination leads to a useful factorization <em>A = LU</em> and how hard a computer will work to invert a very large matrix.</p>
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<h2 class="hd hd-2 unit-title">Lecture Video</h2>
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<h3 class="hd hd-2">Factorization into A = LU</h3>
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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><span style="text-decoration: underline;"><a href="/assets/courseware/v1/93a3d508b63e3792c7e17778d29fb595/asset-v1:OCW+18.06SC+2T2019+type@asset+block/18.06_1.5_LecSum.pdf" target="[object Object]">Factorization into<em> A = LU </em>(PDF)</a></span></li>
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<h3>Suggested Reading </h3>
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<li>Read Section 2.6 in the 4<sup>th</sup> or 5<sup>th</sup> edition.</li>
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<h2 class="hd hd-2 unit-title">Recitation Video</h2>
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<h3 class="hd hd-2">Recitation Video "LU Decomposition" </h3>
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<h2 class="hd hd-2 unit-title">Problems and Solutions</h2>
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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/v1/679fc5c09c516b14f1f58ae5ecea1ea7/asset-v1:OCW+18.06SC+2T2019+type@asset+block/18.06_1.5_Exercises.pdf" target="[object Object]"><span style="text-decoration: underline;">Exercises on factorization into<em> A = LU</em> (PDF)</span></a></p>
<p><a href="/assets/courseware/v1/630be9bd0a2bbb6cb79eadb81a9920c3/asset-v1:OCW+18.06SC+2T2019+type@asset+block/18.06_1.5_Solutions.pdf" target="[object Object]"><span style="text-decoration: underline;">Solutions on factorization into<em> A = LU</em> (PDF)</span></a></p>
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