{"id":28660,"date":"2016-04-02T15:05:39","date_gmt":"2016-04-02T20:05:39","guid":{"rendered":"http:\/\/blogs.ams.org\/mathgradblog\/?p=28660"},"modified":"2016-04-02T15:05:39","modified_gmt":"2016-04-02T20:05:39","slug":"students-abstract-concepts","status":"publish","type":"post","link":"https:\/\/blogs.ams.org\/mathgradblog\/2016\/04\/02\/students-abstract-concepts\/","title":{"rendered":"Getting Students Used to Abstract Concepts"},"content":{"rendered":"<p>According to my experience teaching\u00a0<em>limits<\/em>\u00a0in\u00a0<em>Calculus for Life Scientists,<\/em><em>\u00a0<\/em>it is really difficult for students to understand limits because they do not have the required knowledge on which to build the concept. I have noticed that even if they can handle and apply the limit definition, problems often arise with their supposed prerequisite knowledge such as simplification, least common denominators, factoring, and long division.\u00a0I had to make sure to spend\u00a0the first two weeks of classes reviewing and refreshing\u00a0what they had forgotten from their high school math classes.<\/p>\n<div id=\"attachment_28669\" style=\"width: 289px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-28669\" class=\"size-medium wp-image-28669\" src=\"http:\/\/blogs.ams.org\/mathgradblog\/files\/2016\/04\/function_machine-279x300.png\" alt=\"The function machine by Duane Q. Nykamp is licensed under a Creative Commons Attribution-Noncommercial-ShareAlike 4.0 License (http:\/\/creativecommons.org\/licenses\/by-nc-sa\/4.0\/).\" width=\"279\" height=\"300\" srcset=\"https:\/\/blogs.ams.org\/mathgradblog\/files\/2016\/04\/function_machine-279x300.png 279w, https:\/\/blogs.ams.org\/mathgradblog\/files\/2016\/04\/function_machine.png 500w\" sizes=\"auto, (max-width: 279px) 100vw, 279px\" \/><p id=\"caption-attachment-28669\" class=\"wp-caption-text\">It can take a while for students to become comfortable with the idea\u00a0and practice of treating functions as abstract objects. The function machine by Duane Q. Nykamp is licensed under a Creative Commons Attribution-Noncommercial-ShareAlike 4.0 License (http:\/\/creativecommons.org\/licenses\/by-nc-sa\/4.0\/).<\/p><\/div>\n<p>However, after introducing limits, the students still encountered difficulties understanding the subtleties of one-sided versus two-sided limits. When you explain how to handle <em>some\u00a0<\/em>types of\u00a0functions, students will <!--more-->not pay attention to \u201csome\u201d because they only look at the outside definition without thinking about the internal meaning.\u00a0In the beginning, it helped to give them instructions on how to approach very specific common types of functions such as roots, absolute value functions, piece-wise defined functions, and <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=1%2Fx+&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"1\/x \" class=\"latex\" \/>.<\/p>\n<p>Another way I try\u00a0to decrease the confusion\u00a0for\u00a0my students\u00a0is\u00a0to represent\u00a0the function as a box and tell them that this box is a control system, which means that we have input and output.Therefore, if we have a number or variable as input, this number\/variable needs to be plugged into any variable that appears in the box (I tell them that our function is inside the box). Then, after plugging in whatever we have as input, we will have the result which is the output. It also helps my students when I\u00a0write math problems on the board in colors and sometimes with shapes because it is very helpful for students to focus on the functions and the changes we do to\u00a0them.<\/p>\n<p>Students are familiar with the usage of the variable <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=x&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"x\" class=\"latex\" \/> in functions, say <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=f%28x%29%3Dx%2B5&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"f(x)=x+5\" class=\"latex\" \/>, but if we change that to <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=f%28k%29%3Dk%2B5&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"f(k)=k+5\" class=\"latex\" \/>, some students may not be able to plug in, say <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=%28k%2B1%29&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"(k+1)\" class=\"latex\" \/>, to find <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=f%28k%2B1%29&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"f(k+1)\" class=\"latex\" \/>. To avoid this confusion, I give them at least four examples: one with <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=x&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"x\" class=\"latex\" \/>, one with <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=k&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"k\" class=\"latex\" \/>, one with a Greek letter,\u00a0and one with <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=z&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"z\" class=\"latex\" \/>. This method\u00a0can make students familiar with the usage of other variables in functions.<\/p>\n<p>Similarly, when the students worked in\u00a0groups for a class activity on functions, I noticed some other common mistakes. For example, suppose they are given <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=f%28x%29%3D3%28x%5E2%29+%2B+5&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"f(x)=3(x^2) + 5\" class=\"latex\" \/> and are asked to find <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=f%28x%2Bh%29&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"f(x+h)\" class=\"latex\" \/>. The first time\u00a0I gave them a problem like that, they did not know where to plug in <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=%28x%2Bh%29&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"(x+h)\" class=\"latex\" \/>; often they would\u00a0plug it in as <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=f%28x%2Bh%29%3D3%28x%5E2%29%2B%28h%5E2%29%2B5&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"f(x+h)=3(x^2)+(h^2)+5\" class=\"latex\" \/>. I guided them to the step <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=f%28x%2Bh%29%3D3%28%28x%2Bh%29%5E2%29+%2B5&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"f(x+h)=3((x+h)^2) +5\" class=\"latex\" \/>, but we ended up with another problem because they did\u00a0not know how to simplify <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=%28x%2Bh%29%5E2&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"(x+h)^2\" class=\"latex\" \/>. They thought that <img decoding=\"async\" src=\"https:\/\/s0.wp.com\/latex.php?latex=%28x%2Bh%29%5E2%3Dx%5E2+%2B+h%5E2&#038;bg=ffffff&#038;fg=000&#038;s=0&#038;c=20201002\" alt=\"(x+h)^2=x^2 + h^2\" class=\"latex\" \/>. I always try to help students by writing handouts to address the common errors and how they can avoid making them on exams. (You can view the handout that I created on this topic\u00a0<a href=\"http:\/\/media.wix.com\/ugd\/ae1416_44e5f63371df411b8ea0a5ab4ca5ef89.pdf\" target=\"_blank\">here<\/a>.)\u00a0 When\u00a0I see something is very\u00a0difficult for them to understand using the traditional method, I create my own method\u00a0using\u00a0interactive\u00a0techniques. (See my earlier blog post: <em><a href=\"http:\/\/blogs.ams.org\/mathgradblog\/2016\/01\/03\/change-traditional-mathematics-teaching-memorization-based-method-interactive-based-method\/#sthash.mYFlVAxZ.dpbs\">How to change the Traditional Mathematics Teaching from the Memorization-Based Method to Interactive-Based Method<\/a>.)<\/em><\/p>\n<p>In conclusion, based on my experience, handling functions as abstract objects is one of the most difficult mathematical concepts for non-engineering and non-math students. I believe that a successful math teacher must teach students how to use advanced mathematical thinking in order to help them become more comfortable\u00a0with abstract mathematical objects.<\/p>\n<p>To see more teaching handouts, please see\u00a0<a href=\"http:\/\/www.mohammed-kaabar.net\/#!calculus-for-life-scientists-lab-sectio\/cyl7\">my course webpage<\/a>. Best of luck and feel free to reach out if you have questions!<\/p>\n<p>&nbsp;<\/p>\n<div style=\"margin-top: 0px; margin-bottom: 0px;\" class=\"sharethis-inline-share-buttons\" ><\/div>","protected":false},"excerpt":{"rendered":"<p>According to my experience teaching\u00a0limits\u00a0in\u00a0Calculus for Life Scientists,\u00a0it is really difficult for students to understand limits because they do not have the required knowledge on which to build the concept. I have noticed that even if they can handle and &hellip; <a href=\"https:\/\/blogs.ams.org\/mathgradblog\/2016\/04\/02\/students-abstract-concepts\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n<div style=\"margin-top: 0px; margin-bottom: 0px;\" class=\"sharethis-inline-share-buttons\" data-url=https:\/\/blogs.ams.org\/mathgradblog\/2016\/04\/02\/students-abstract-concepts\/><\/div>\n","protected":false},"author":94,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[2,158,157,20],"tags":[200,134,135],"class_list":["post-28660","post","type-post","status-publish","format-standard","hentry","category-advice","category-math-education","category-math-teaching","category-teaching","tag-calculus","tag-math-education","tag-teaching-advice"],"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p3gbww-7sg","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/blogs.ams.org\/mathgradblog\/wp-json\/wp\/v2\/posts\/28660","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.ams.org\/mathgradblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.ams.org\/mathgradblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.ams.org\/mathgradblog\/wp-json\/wp\/v2\/users\/94"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.ams.org\/mathgradblog\/wp-json\/wp\/v2\/comments?post=28660"}],"version-history":[{"count":23,"href":"https:\/\/blogs.ams.org\/mathgradblog\/wp-json\/wp\/v2\/posts\/28660\/revisions"}],"predecessor-version":[{"id":28665,"href":"https:\/\/blogs.ams.org\/mathgradblog\/wp-json\/wp\/v2\/posts\/28660\/revisions\/28665"}],"wp:attachment":[{"href":"https:\/\/blogs.ams.org\/mathgradblog\/wp-json\/wp\/v2\/media?parent=28660"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.ams.org\/mathgradblog\/wp-json\/wp\/v2\/categories?post=28660"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.ams.org\/mathgradblog\/wp-json\/wp\/v2\/tags?post=28660"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}