{"id":30241,"date":"2018-02-21T17:45:10","date_gmt":"2018-02-21T17:45:10","guid":{"rendered":"http:\/\/www.oracletutoring.ca\/blog\/?p=30241"},"modified":"2018-02-21T17:45:10","modified_gmt":"2018-02-21T17:45:10","slug":"calculator-usage-negative-numbers-to-rational-exponents-with-odd-roots","status":"publish","type":"post","link":"https:\/\/www.oracletutoring.ca\/blog\/calculator-usage-negative-numbers-to-rational-exponents-with-odd-roots\/","title":{"rendered":"Calculator usage: negative numbers to rational exponents (with odd roots)"},"content":{"rendered":"

Tutoring high school math, scientific calculators are a permanent fascination. The tutor mentions a quirk many might share.<\/h1>\n

Due to<\/p>\n

<\/p>\n

and the fact that a common exponent notation is<\/p>\n

\nxa<\/sup>=x^a,\n<\/p>\n

it follows that<\/p>\n

(-8)^(2\/3)=4.<\/p>\n

Curiously, of all the calculators in front of me this moment, only two – the Casio fx-991ES PLUS C and the TI-83 Plus (a graphing calculator) – are willing to perform (-8)^(2\/3) as presented. The others give “ERROR”.<\/p>\n

Yet, invoking the rule shown above, we can rewrite the calculation as<\/p>\n

3<\/sup>√(-8)2<\/sup><\/p>\n

Then, all the scientific calculators I have at hand will give the answer 4. However, the calculator aboard my mobile phone will only do so if the square is posed before the cube root.<\/p>\n

HTH:)<\/p>\n

Jack of Oracle Tutoring by Jack and Diane,<\/a> Campbell River, BC<\/p>\n","protected":false},"excerpt":{"rendered":"

Tutoring high school math, scientific calculators are a permanent fascination. The tutor mentions a quirk many might share. Due to and the fact that a common exponent notation is xa=x^a, it follows that (-8)^(2\/3)=4. Curiously, of all the calculators in …<\/p>\n

Calculator usage: negative numbers to rational exponents (with odd roots)<\/span> Read More »<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[90,3,1],"tags":[2743,2741],"class_list":["post-30241","post","type-post","status-publish","format-standard","hentry","category-calculator-usage","category-math","category-uncategorized","tag-rewriting-rational-exponent-so-calculator-will-accept-it","tag-some-calculators-wont-do-negative-number-to-rational-exponent-even-when-its-defined"],"_links":{"self":[{"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/posts\/30241","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=30241"}],"version-history":[{"count":46,"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/posts\/30241\/revisions"}],"predecessor-version":[{"id":30287,"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/posts\/30241\/revisions\/30287"}],"wp:attachment":[{"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/media?parent=30241"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/categories?post=30241"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.oracletutoring.ca\/blog\/wp-json\/wp\/v2\/tags?post=30241"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}