{"id":6272,"date":"2024-04-02T19:26:34","date_gmt":"2024-04-03T01:26:34","guid":{"rendered":"https:\/\/augerhandle.net\/blogs\/jumpingfish\/?p=6272"},"modified":"2024-04-02T19:38:53","modified_gmt":"2024-04-03T01:38:53","slug":"a-calculus-side-hustle","status":"publish","type":"post","link":"https:\/\/augerhandle.net\/blogs\/jumpingfish\/2024\/04\/02\/a-calculus-side-hustle\/","title":{"rendered":"A Calculus Side Hustle"},"content":{"rendered":"<h3>1.<\/h3>\n<p>It was the beginning of seventh period. The tardy bell was about to ring. Reginald came into the room. What was he doing here? He&rsquo;s in second period.<\/p>\n<p>&ldquo;Hi Reginald. What&rsquo;s up?&#8221;<\/p>\n<p>&ldquo;Well&#8230; what do you have for me today?&#8221;<\/p>\n<p>He had a smirk on his face that stayed glued there.&nbsp;<\/p>\n<h3>2.<\/h3>\n<p>Reginald is a bright student. He grasps the algebra almost before I finish speaking, sometimes completing my sentences. A few weeks ago, he proudly showed off some work he had been doing with limits. He&#8217;s hungry for more than algebra, so we work together a few times a week.<\/p>\n<p>After it was clear that he had a solid understanding of limits, we started discussing derivatives. He had heard of them, but not in the way I had in mind. I taught him the definition of derivatives in terms of limits. We worked an example together. He ate it up. Then he did one on his own. And another.<\/p>\n<p>I gave him an assignment. &ldquo;Come back and show me what you find.&#8221;<\/p>\n<h3>3.<\/h3>\n<p>The next day he was back, going on about Taylor series and showing me his cosine and sine expansions.<\/p>\n<p>&ldquo;I&rsquo;m not sure what this means,&rdquo; he said, pointing to factorial terms like&nbsp;<em>2!<\/em> and <em>4!<\/em> in the denominators of some of the fractions. So we talked about them. And then we talked about taking the derivatives of the terms in the series one at a time. And then we were out of time.<\/p>\n<p>&ldquo;Take what you understand, and see if you can figure out what the derivative of <em>sin(x)<\/em> is.&rdquo; I gave him a couple hints and jotted down some things on a piece of paper which I held out to him.<\/p>\n<p>&ldquo;Oh I don&rsquo;t need that,&rdquo; he said. He had already absorbed it all.<\/p>\n<h3>4.<\/h3>\n<p>When he returned, he held out a sheet of paper where he had written the series expansion for <em>sin(x)<\/em> and taken the derivative of each of the terms and done some factoring. At the bottom of the page was his result: the derivative of <em>sin(x)<\/em> is <em>cos(x)<\/em>.<\/p>\n<p>The next time he came back with the derivative of <em>sin(-x<\/em>). And with very little prompting he was soon calculating the derivatives of <em>sin(kx)<\/em> and <em>sin(-kx)<\/em> and <em>cos(x) <\/em>and<em> cos(-x) <\/em>and<em> cos(kx)<\/em>. And I was running out of things for us to talk about. After all, I just teach algebra.&nbsp;<\/p>\n<h3>5.<\/h3>\n<p>So there we were. And when he asked, &ldquo;Well&#8230; what do you have for me today?&rdquo; with a smirk on his face, waiting for me to serve up the next calculus lesson, I was prepared.&nbsp;<\/p>\n<p>We sketched some things on the board. I gave him the assignment of finding the derivative of <em>sin(x)<\/em> without using the Taylor series expansion that he had become so adept at manipulating. I suggested that he look it up online, figure out all the steps, and then come back and teach it to me.<\/p>\n<p>&ldquo;Hmmm&#8230;&rdquo; he said, evidently intrigued at the notion that there might be another way.<\/p>\n<p>It didn&rsquo;t take long. He came back to report the results of his researches.&nbsp;<\/p>\n<p>And now I really am running out of things to discuss. I don&rsquo;t have the time. I think I&rsquo;ll introduce him to hyperbolic trig functions, <em>sinh(x)<\/em> and <em>cosh(x)<\/em>. Maybe that will win me a week or so.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>1. It was the beginning of seventh period. The tardy bell was about to ring. Reginald came into the room. What was he doing here? He&rsquo;s in second period. &ldquo;Hi Reginald. What&rsquo;s up?&#8221; &ldquo;Well&#8230; what do you have for me today?&#8221; He had a smirk on his face that stayed glued there.&nbsp; 2. Reginald is [&hellip;]<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[],"tags":[],"_links":{"self":[{"href":"https:\/\/augerhandle.net\/blogs\/jumpingfish\/wp-json\/wp\/v2\/posts\/6272"}],"collection":[{"href":"https:\/\/augerhandle.net\/blogs\/jumpingfish\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/augerhandle.net\/blogs\/jumpingfish\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/augerhandle.net\/blogs\/jumpingfish\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/augerhandle.net\/blogs\/jumpingfish\/wp-json\/wp\/v2\/comments?post=6272"}],"version-history":[{"count":2,"href":"https:\/\/augerhandle.net\/blogs\/jumpingfish\/wp-json\/wp\/v2\/posts\/6272\/revisions"}],"predecessor-version":[{"id":6274,"href":"https:\/\/augerhandle.net\/blogs\/jumpingfish\/wp-json\/wp\/v2\/posts\/6272\/revisions\/6274"}],"wp:attachment":[{"href":"https:\/\/augerhandle.net\/blogs\/jumpingfish\/wp-json\/wp\/v2\/media?parent=6272"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/augerhandle.net\/blogs\/jumpingfish\/wp-json\/wp\/v2\/categories?post=6272"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/augerhandle.net\/blogs\/jumpingfish\/wp-json\/wp\/v2\/tags?post=6272"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}