{"id":10488,"date":"2025-05-05T10:00:00","date_gmt":"2025-05-05T15:00:00","guid":{"rendered":"https:\/\/blog.lib.uiowa.edu\/eng\/?p=10488"},"modified":"2025-05-02T11:33:40","modified_gmt":"2025-05-02T16:33:40","slug":"happy-square-root-day","status":"publish","type":"post","link":"http:\/\/blog.lib.uiowa.edu\/eng\/happy-square-root-day\/","title":{"rendered":"Happy Square Root Day!\u00a0"},"content":{"rendered":"\n<p><span data-contrast=\"auto\">Today is 5\/5\/25, making it Square Root Day because 5 x 5 = 25. The last Square Root Day was 4\/4\/16 and our next one will be 6\/6\/36. Here are some fun square root facts that you can share today:<\/span><span data-ccp-props=\"{}\">&nbsp;<\/span><\/p>\n<ul>\n<li data-leveltext=\"\uf0b7\" data-font=\"Symbol\" data-listid=\"1\" data-list-defn-props=\"{&quot;335552541&quot;:1,&quot;335559685&quot;:720,&quot;335559991&quot;:360,&quot;469769226&quot;:&quot;Symbol&quot;,&quot;469769242&quot;:[8226],&quot;469777803&quot;:&quot;left&quot;,&quot;469777804&quot;:&quot;\uf0b7&quot;,&quot;469777815&quot;:&quot;hybridMultilevel&quot;}\" data-aria-posinset=\"1\" data-aria-level=\"1\"><span data-contrast=\"auto\">A whole number with a square root that is also a whole number is called a perfect square. The days on which we celebrate Square Root Day are all examples of perfect squares, since we don\u2019t have decimal days or months.<\/span><span data-ccp-props=\"{}\">&nbsp;<\/span><\/li>\n<\/ul>\n<ul>\n<li data-leveltext=\"\uf0b7\" data-font=\"Symbol\" data-listid=\"1\" data-list-defn-props=\"{&quot;335552541&quot;:1,&quot;335559685&quot;:720,&quot;335559991&quot;:360,&quot;469769226&quot;:&quot;Symbol&quot;,&quot;469769242&quot;:[8226],&quot;469777803&quot;:&quot;left&quot;,&quot;469777804&quot;:&quot;\uf0b7&quot;,&quot;469777815&quot;:&quot;hybridMultilevel&quot;}\" data-aria-posinset=\"2\" data-aria-level=\"1\"><span data-contrast=\"auto\">Negative numbers do not have square roots, since multiplying a number by itself will always give a positive (i.e. -4 x \u20134 = 16). However, you can express the square root of a negative number by using imaginary numbers (4<\/span><i><span data-contrast=\"auto\">i<\/span><\/i><span data-contrast=\"auto\"> x 4<\/span><i><span data-contrast=\"auto\">i = <\/span><\/i><span data-contrast=\"auto\">-16).<\/span><span data-ccp-props=\"{}\">&nbsp;<\/span><\/li>\n<\/ul>\n<ul>\n<li data-leveltext=\"\uf0b7\" data-font=\"Symbol\" data-listid=\"1\" data-list-defn-props=\"{&quot;335552541&quot;:1,&quot;335559685&quot;:720,&quot;335559991&quot;:360,&quot;469769226&quot;:&quot;Symbol&quot;,&quot;469769242&quot;:[8226],&quot;469777803&quot;:&quot;left&quot;,&quot;469777804&quot;:&quot;\uf0b7&quot;,&quot;469777815&quot;:&quot;hybridMultilevel&quot;}\" data-aria-posinset=\"3\" data-aria-level=\"1\"><span data-contrast=\"auto\">We don\u2019t know where exactly the square root symbol came from. Some theories say Arab mathematicians used the first letter in the Arabic word for root, while others believe it came from the Latin letter \u201cr,\u201d which is also the first letter in the Latin word for root.&nbsp;<\/span><span data-ccp-props=\"{}\">&nbsp;<\/span><\/li>\n<\/ul>\n<ul>\n<li data-leveltext=\"\uf0b7\" data-font=\"Symbol\" data-listid=\"1\" data-list-defn-props=\"{&quot;335552541&quot;:1,&quot;335559685&quot;:720,&quot;335559991&quot;:360,&quot;469769226&quot;:&quot;Symbol&quot;,&quot;469769242&quot;:[8226],&quot;469777803&quot;:&quot;left&quot;,&quot;469777804&quot;:&quot;\uf0b7&quot;,&quot;469777815&quot;:&quot;hybridMultilevel&quot;}\" data-aria-posinset=\"4\" data-aria-level=\"1\"><span data-contrast=\"auto\">The radix we use today was created by Descartes, who combined two previously used notation symbols.&nbsp;<\/span><span data-ccp-props=\"{}\">&nbsp;<\/span><\/li>\n<li data-leveltext=\"\uf0b7\" data-font=\"Symbol\" data-listid=\"1\" data-list-defn-props=\"{&quot;335552541&quot;:1,&quot;335559685&quot;:720,&quot;335559991&quot;:360,&quot;469769226&quot;:&quot;Symbol&quot;,&quot;469769242&quot;:[8226],&quot;469777803&quot;:&quot;left&quot;,&quot;469777804&quot;:&quot;\uf0b7&quot;,&quot;469777815&quot;:&quot;hybridMultilevel&quot;}\" data-aria-posinset=\"5\" data-aria-level=\"1\"><span data-contrast=\"auto\">The ancient Mesopotamians might have calculated a square root approximation by using a sequence of rectangles(<\/span><span data-contrast=\"auto\">1)<\/span><span data-contrast=\"auto\">. There\u2019s a Mesopotamian tablet from the Old Babylonian period that contains square root calculations expressed exclusively with vertical wedges representing ones and tens arranged relationally to each other.(<\/span><span data-contrast=\"auto\">2)<\/span> <span data-ccp-props=\"{}\">&nbsp;<\/span><\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/blog.lib.uiowa.edu\/eng\/files\/2025\/05\/image.jpg\"><img loading=\"lazy\" decoding=\"async\" width=\"654\" height=\"298\" src=\"https:\/\/blog.lib.uiowa.edu\/eng\/files\/2025\/05\/image.jpg\" alt=\"A paper figure with three parts. The first part is labeled &quot;Transcription&quot; and contains a list of numbers. The second is labeled &quot;Calculations&quot; and takes those numbers from the first section and illustrates how they are part of a square root calculation. The third section is labeled &quot;copy&quot; and features a circle enclosing a series of cuneiform markings - long lines, some in groups, with perpendicular tops.\" class=\"wp-image-10492\" srcset=\"http:\/\/blog.lib.uiowa.edu\/eng\/files\/2025\/05\/image.jpg 654w, http:\/\/blog.lib.uiowa.edu\/eng\/files\/2025\/05\/image-300x137.jpg 300w\" sizes=\"(max-width: 654px) 100vw, 654px\" \/><\/a><figcaption class=\"wp-element-caption\">Christine Proust. INTERPRETATION OF REVERSE ALGORITHMS IN SEVERAL<br>MESOPOTAMIAN TEXTS. Karine Chemla. The History of Mathematical Proof in Ancient Traditions, 2012. ffhal-01139635f<\/figcaption><\/figure>\n\n\n\n<p>Special thanks to collaborator Carol Hollier from the Sciences Library for her contributions to this blog post.<\/p>\n<p>References:<\/p>\n<ol>\n<li><span class=\"TextRun SCXW121677269 BCX0\" lang=\"EN-US\" xml:lang=\"EN-US\" data-contrast=\"auto\"><span class=\"NormalTextRun SCXW121677269 BCX0\" data-ccp-parastyle=\"footnote text\">Daniel F. Mansfield (2023) Mesopotamian square root approximation by a sequence of rectangles, British Journal for the History of Mathematics, 38:3, 175-188, DOI: 10.1080\/26375451.2023.2215652<\/span><\/span><span class=\"EOP SCXW121677269 BCX0\" data-ccp-props=\"{&quot;201341983&quot;:0,&quot;335559739&quot;:0,&quot;335559740&quot;:240}\">\u00a0<\/span><\/li>\n<li><span class=\"TextRun SCXW99277059 BCX0\" lang=\"EN-US\" xml:lang=\"EN-US\" data-contrast=\"auto\"><span class=\"NormalTextRun SCXW99277059 BCX0\" data-ccp-parastyle=\"footnote text\">C. Proust, Interpretation of reverse algorithms in several Mesopotamian texts, in\u00a0<\/span><span class=\"NormalTextRun SCXW99277059 BCX0\" data-ccp-parastyle=\"footnote text\">The<\/span><span class=\"NormalTextRun SCXW99277059 BCX0\" data-ccp-parastyle=\"footnote text\">\u00a0history of mathematical proof in ancient traditions,\u00a0<\/span><span class=\"NormalTextRun SCXW99277059 BCX0\" data-ccp-parastyle=\"footnote text\">384&#8211;422<\/span><span class=\"NormalTextRun SCXW99277059 BCX0\" data-ccp-parastyle=\"footnote text\">, translated by Micah Ross, Cambridge Univ. Press.<\/span><span class=\"NormalTextRun SCXW99277059 BCX0\" data-ccp-parastyle=\"footnote text\">\u00a0 See chart on page 21 of the preprint:\u00a0<\/span><\/span><a class=\"Hyperlink SCXW99277059 BCX0\" href=\"https:\/\/hal.science\/hal-01139635\/file\/12Proust-pp.pdf\" target=\"_blank\" rel=\"noreferrer noopener\"><span class=\"TextRun Underlined SCXW99277059 BCX0\" lang=\"EN-US\" xml:lang=\"EN-US\" data-contrast=\"none\"><span class=\"NormalTextRun SCXW99277059 BCX0\" data-ccp-charstyle=\"Hyperlink\">https:\/\/hal.science\/hal-01139635\/file\/12Proust-pp.pdf<\/span><\/span><\/a><span class=\"EOP SCXW99277059 BCX0\" data-ccp-props=\"{&quot;201341983&quot;:0,&quot;335559739&quot;:0,&quot;335559740&quot;:240}\">\u00a0<\/span><\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"<p>Today is 5\/5\/25, making it Square Root Day because 5 x 5 = 25. The last Square Root Day was 4\/4\/16 and our next one will be 6\/6\/36. Here are some fun square root facts that you can share today:&nbsp; A whole number with a square root that is also a whole number is called<a class=\"more-link\" href=\"http:\/\/blog.lib.uiowa.edu\/eng\/happy-square-root-day\/\">Continue reading <span class=\"screen-reader-text\">&#8220;Happy Square Root Day!\u00a0&#8220;<\/span><\/a><\/p>\n","protected":false},"author":309,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"syndication":[72],"_links":{"self":[{"href":"http:\/\/blog.lib.uiowa.edu\/eng\/wp-json\/wp\/v2\/posts\/10488"}],"collection":[{"href":"http:\/\/blog.lib.uiowa.edu\/eng\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/blog.lib.uiowa.edu\/eng\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/blog.lib.uiowa.edu\/eng\/wp-json\/wp\/v2\/users\/309"}],"replies":[{"embeddable":true,"href":"http:\/\/blog.lib.uiowa.edu\/eng\/wp-json\/wp\/v2\/comments?post=10488"}],"version-history":[{"count":2,"href":"http:\/\/blog.lib.uiowa.edu\/eng\/wp-json\/wp\/v2\/posts\/10488\/revisions"}],"predecessor-version":[{"id":10493,"href":"http:\/\/blog.lib.uiowa.edu\/eng\/wp-json\/wp\/v2\/posts\/10488\/revisions\/10493"}],"wp:attachment":[{"href":"http:\/\/blog.lib.uiowa.edu\/eng\/wp-json\/wp\/v2\/media?parent=10488"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/blog.lib.uiowa.edu\/eng\/wp-json\/wp\/v2\/categories?post=10488"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/blog.lib.uiowa.edu\/eng\/wp-json\/wp\/v2\/tags?post=10488"},{"taxonomy":"syndication","embeddable":true,"href":"http:\/\/blog.lib.uiowa.edu\/eng\/wp-json\/wp\/v2\/syndication?post=10488"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}