{"id":20055,"date":"2017-02-12T17:43:27","date_gmt":"2017-02-12T17:43:27","guid":{"rendered":"http:\/\/www.oracletutoring.ca\/blog\/?p=20055"},"modified":"2017-02-12T17:43:27","modified_gmt":"2017-02-12T17:43:27","slug":"spreadsheets-excel-and-libreoffice-calc-the-sum-of-a-geometric-series","status":"publish","type":"post","link":"https:\/\/www.oracletutoring.ca\/blog\/spreadsheets-excel-and-libreoffice-calc-the-sum-of-a-geometric-series\/","title":{"rendered":"Spreadsheets:  Excel and LibreOffice Calc:  the sum of a geometric series"},"content":{"rendered":"<h1>The tutor shows the seriessum() function, found on both Excel and LibreOffice Calc.<\/h1>\n<p>A geometric series has the form<\/p>\n<p style=\"text-align:center\">S<sub>n<\/sub> = cr<sup>0<\/sup> + cr<sup>1<\/sup> + &#8230; + cr<sup>n-1<\/sup><\/p>\n<p>An example is<\/p>\n<p>3 + 3*4 + 3*4<sup>2<\/sup> + &#8230; + 3*4<sup>5<\/sup><\/p>\n<p>which might also be written<\/p>\n<p>3 + 12 + 48 + 192 + 768 + 3072<\/p>\n<p>With Excel or LibreOffice Calc, the function to evaluate that sum is <strong>=seriessum(a,b,c,d)<\/strong>, where<\/p>\n<ul>\n<li>\na is the number whose exponent increases each term (4, in the example just above)<\/li>\n<li>\nb is the initial exponent of a (0, in the example just above)<\/li>\n<li>\nc is the increment by which the exponent increases each term (1, in the example just above)<\/li>\n<li>\nd is an array of the coefficients of the terms.  In the example just above, the coefficient is always 3.  You&#8217;d need to enter {3,3,3,3,3,3} for d:  one 3 for each term.<\/li>\n<\/ul>\n<p>So, to evaluate 3 + 12 + 48 + 192 + 768 + 3072, you might enter<\/p>\n<p style=\"font-family:monospace;font-size:120%\">=seriessum(4,0,1,{3,3,3,3,3,3})<\/p>\n<p>Hopefully you receive the answer 4095:)<\/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 shows the seriessum() function, found on both Excel and LibreOffice Calc. A geometric series has the form Sn = cr0 + cr1 + &#8230; + crn-1 An example is 3 + 3*4 + 3*42 + &#8230; + 3*45 &hellip;<\/p>\n<p class=\"read-more\"> <a class=\"more-link\" href=\"https:\/\/www.oracletutoring.ca\/blog\/spreadsheets-excel-and-libreoffice-calc-the-sum-of-a-geometric-series\/\"> <span class=\"screen-reader-text\">Spreadsheets:  Excel and LibreOffice Calc:  the sum of a geometric series<\/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":[1583,1951,3],"tags":[],"class_list":["post-20055","post","type-post","status-publish","format-standard","hentry","category-excel","category-libreoffice-calc","category-math"],"_links":{"self":[{"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/posts\/20055","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=20055"}],"version-history":[{"count":13,"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/posts\/20055\/revisions"}],"predecessor-version":[{"id":20068,"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/posts\/20055\/revisions\/20068"}],"wp:attachment":[{"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/media?parent=20055"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/categories?post=20055"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/tags?post=20055"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}