{"id":15310,"date":"2016-04-19T18:53:40","date_gmt":"2016-04-19T18:53:40","guid":{"rendered":"http:\/\/www.oracletutoring.ca\/blog\/?p=15310"},"modified":"2018-01-27T19:21:55","modified_gmt":"2018-01-27T19:21:55","slug":"calculus-the-limit-as-n-tends-to-infinity-of-nth-root-of-n","status":"publish","type":"post","link":"https:\/\/www.oracletutoring.ca\/blog\/calculus-the-limit-as-n-tends-to-infinity-of-nth-root-of-n\/","title":{"rendered":"Calculus: the limit, as n tends to infinity, of nth root of n."},"content":{"rendered":"<h1>The tutor works a limit using the log trick and l&#8217;H\u00f4pital&#8217;s rule.<\/h1>\n<p><strong>Example:<\/strong>  Evaluate lim<sub>n\u2192\u221e<\/sub>n^(1\/n)<\/p>\n<p>Solution:<\/p>\n<p>First, imagine<\/p>\n<p>y=lim<sub>n\u2192\u221e<\/sub>n^(1\/n)<\/p>\n<p>Next, we take the logarithm of both sides:<\/p>\n<p>lny=lnlim<sub>n\u2192\u221e<\/sub>n^(1\/n)<\/p>\n<p>Now, because both lny and n^(1\/n) are continuous n\u2192\u221e, we can change their order on the right side:<\/p>\n<p>lny=lim<sub>n\u2192\u221e<\/sub>lnn^(1\/n)<\/p>\n<p>Using the log rule about exponent-to-multiple gives<\/p>\n<p>lny=lim<sub>n\u2192\u221e<\/sub>(1\/n)lnn<\/p>\n<p>or<\/p>\n<p>lny=lim<sub>n\u2192\u221e<\/sub>lnn\/n<\/p>\n<p>This limit has the \u221e\/\u221e form, which means, by l&#8217;H\u00f4pital&#8217;s Rule, we can take the derivative of the numerator and denominator separately, then take the limit of that result:<\/p>\n<p>lny=lim<sub>n\u2192\u221e<\/sub>(1\/n)\/1=lim<sub>n\u2192\u221e<\/sub>(1\/n)<\/p>\n<p>So,<\/p>\n<p>lny = 0<\/p>\n<p>We take the exponential of both sides:<\/p>\n<p>e^(lny) = e^0<\/p>\n<p>to arrive at<\/p>\n<p>y=1<\/p>\n<p>Recalling that y=lim<sub>n\u2192\u221e<\/sub>(1\/n), we realize that<\/p>\n<p>lim<sub>n\u2192\u221e<\/sub>n^(1\/n)=1<\/p>\n<p>HTH:)<\/p>\n<p>Source:<\/p>\n<p>Larson, Roland E. and Robert P. Hostetler.  <u>Calculus<\/u>.  Toronto:<br \/>\u00a0\u00a0  D.C. Heath and Company, Ltd., 1986.<\/p>\n<p>Jack of <a href=\"https:\/\/www.oracletutoring.ca\">Oracle Tutoring by Jack and Diane,<\/a> Campbell River, BC.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The tutor works a limit using the log trick and l&#8217;H\u00f4pital&#8217;s rule. Example: Evaluate limn\u2192\u221en^(1\/n) Solution: First, imagine y=limn\u2192\u221en^(1\/n) Next, we take the logarithm of both sides: lny=lnlimn\u2192\u221en^(1\/n) Now, because both lny and n^(1\/n) are continuous n\u2192\u221e, we can change &hellip;<\/p>\n<p class=\"read-more\"> <a class=\"more-link\" href=\"https:\/\/www.oracletutoring.ca\/blog\/calculus-the-limit-as-n-tends-to-infinity-of-nth-root-of-n\/\"> <span class=\"screen-reader-text\">Calculus: the limit, as n tends to infinity, of nth root of n.<\/span> Read More &raquo;<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[234],"tags":[1570],"class_list":["post-15310","post","type-post","status-publish","format-standard","hentry","category-calculus","tag-limit-of-nth-root-of-n-as-n-goes-to-infinity"],"_links":{"self":[{"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/posts\/15310","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/comments?post=15310"}],"version-history":[{"count":24,"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/posts\/15310\/revisions"}],"predecessor-version":[{"id":28796,"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/posts\/15310\/revisions\/28796"}],"wp:attachment":[{"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/media?parent=15310"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/categories?post=15310"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/tags?post=15310"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}