{"id":7667,"date":"2022-09-16T07:01:47","date_gmt":"2022-09-16T07:01:47","guid":{"rendered":"https:\/\/mdr.foobrdigital.com\/?p=7667"},"modified":"2022-09-16T07:01:47","modified_gmt":"2022-09-16T07:01:47","slug":"trig-functions-in-the-cartesian-plane","status":"publish","type":"post","link":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/2022\/09\/16\/trig-functions-in-the-cartesian-plane\/","title":{"rendered":"Trig. Functions in the Cartesian Plane"},"content":{"rendered":"\n<p>In these lessons, we will look at Trigonometric Functions for any angle in the Cartesian Plane by using the reference angle.<\/p>\n\n\n\n<p>Steps to solving trigonometric functions for any angle<\/p>\n\n\n\n<p><strong>Step 1:<\/strong>\u00a0Find the\u00a0Reference Angle, which is always acute<br><strong>Step 2:\u00a0<\/strong>Find Trig Function Value for the reference angle<br><strong>Step 3:\u00a0<\/strong>Determine the Sign (positive or negative) of the trig function based on the quadrant<\/p>\n\n\n\n<p><strong><em>Example:<\/em><\/strong><\/p>\n\n\n\n<p>Find<br>a) sin 120\u00b0<br>b) cos 150\u00b0<br>c) tan 210\u00b0<br>d) csc 300\u00b0<\/p>\n\n\n\n<p><strong><em>Solution:<\/em><\/strong><\/p>\n\n\n\n<p>a) sin 120\u00b0<br><strong>Step 1:&nbsp;<\/strong>Find the reference angle<br>180\u00b0 \u2013 120\u00b0 = 60\u00b0<\/p>\n\n\n\n<p><strong>Step 2:&nbsp;<\/strong>Find Trig Function Value for the reference angle<br>sin 60\u00b0 = 0.866<\/p>\n\n\n\n<p><strong>Step 3:<\/strong>&nbsp;Determine the Sign (positive or negative) of the trig function based on the quadrant<br>120\u00b0 is in the second quadrant, where sin is positive.<\/p>\n\n\n\n<p>So, sin 120\u00b0 = sin 60\u00b0 = 0.866<br><br>b) cos 150\u00b0<\/p>\n\n\n\n<p><strong>Step 1:<\/strong>&nbsp;Find the reference angle<br>180\u00b0 \u2013 150\u00b0 = 30\u00b0<\/p>\n\n\n\n<p><strong>Step 2:<\/strong>&nbsp;Find Trig Function Value for the reference angle<br>cos 30\u00b0 = 0.866<\/p>\n\n\n\n<p><strong>Step 3:&nbsp;<\/strong>Determine the Sign (positive or negative) of the trig function based on the quadrant<br>150\u00b0 is in the second quadrant, where cos is negative<\/p>\n\n\n\n<p>So, cos 150\u00b0 = \u2013cos 30\u00b0 = \u20130.866<\/p>\n\n\n\n<p>c) tan 210\u00b0<\/p>\n\n\n\n<p><strong>Step 1:&nbsp;<\/strong>Find the reference angle<br>210\u00b0 \u2013 180\u00b0 = 30\u00b0<\/p>\n\n\n\n<p><strong>Step 2:&nbsp;<\/strong>Find Trig Function Value for the reference angle<br>tan 30\u00b0 = 0.5774<\/p>\n\n\n\n<p><strong>Step 3:<\/strong>&nbsp;Determine the Sign (positive or negative) of the trig function based on the quadrant<br>210\u00b0 is in the third quadrant, where tan is positive<\/p>\n\n\n\n<p>So, tan 210\u00b0 = tan 30\u00b0 = 0.5774<\/p>\n\n\n\n<p>d) csc 300\u00b0<\/p>\n\n\n\n<p><strong>Step 1:&nbsp;<\/strong>Find the reference angle<br>360\u00b0 \u2013 300\u00b0 = 60\u00b0<\/p>\n\n\n\n<p><strong>Step 2:<\/strong>&nbsp;Find Trig Function Value for the reference angle<br>csc 60\u00b0 = 1.155<\/p>\n\n\n\n<p><strong>Step 3:&nbsp;<\/strong>Determine the Sign (positive or negative) of the trig function based on the quadrant<br>300\u00b0 is in the fourth quadrant, where csc is negative<\/p>\n\n\n\n<p>So, csc 300\u00b0 = \u2013csc 60\u00b0 = \u20131.155<\/p>\n\n\n\n<p><strong><em>Example:<\/em><\/strong><\/p>\n\n\n\n<p>Given that sin 56\u02da = 0.83 and cos 56\u02da = 0.56, find the value of<br>2 sin 304\u02da + cos 124\u02da<\/p>\n\n\n\n<p><em><strong>Solution<\/strong><\/em><strong><em>&nbsp;:<\/em><\/strong><\/p>\n\n\n\n<p>Reference angle for 304\u02da = (360\u02da \u2013 304\u02da) = 56\u02da<br>sin 304\u02da = \u2013 (sin 56\u02da) = \u20130.83<\/p>\n\n\n\n<p>Reference angle for 124\u02da = (180\u02da \u2013 124\u02da) = 56\u02da<br>cos 124\u02da = \u2013 (cos 56\u02da) = \u20130.56<\/p>\n\n\n\n<p>2 sin 304\u02da + cos 124\u02da = 2 (\u20130.83) + (\u20130.56) =&nbsp;<strong>\u20132.22<\/strong><\/p>\n\n\n\n<p><strong><em>Example:<\/em><\/strong><\/p>\n\n\n\n<p>Given that 0\u02da \u2264&nbsp;<em>x<\/em>&nbsp;\u2264 360 \u02da, find the angle&nbsp;<em>x<\/em>&nbsp;for each of the following:<\/p>\n\n\n\n<p>a) sin&nbsp;<em>x<\/em>&nbsp;= \u20130.6691<br>b) cos&nbsp;<em>x<\/em>&nbsp;= 0.2079<br>c) tan&nbsp;<em>x<\/em>&nbsp;= \u20131.4281<\/p>\n\n\n\n<p><strong><em>Solution:<\/em><\/strong><\/p>\n\n\n\n<p>a) sin&nbsp;<em>x<\/em>&nbsp;= \u20130.6691<\/p>\n\n\n\n<p>reference angle = sin -1 (0.6691)<br>reference angle = 42\u02da (round to the nearest degree)<\/p>\n\n\n\n<p>sin is negative in the quadrant III and IV<br>So,&nbsp;<em>x<\/em>&nbsp;= 180 + 42 = 222\u02da or<br><em>x<\/em>&nbsp;= 360 \u2013 42 = 318\u02da<\/p>\n\n\n\n<p>b) cos&nbsp;<em>x<\/em>&nbsp;= 0.2079<\/p>\n\n\n\n<p>reference angle = cos -1 (0.2079)<br>reference angle = 78\u02da (round to the nearest degree)<\/p>\n\n\n\n<p>cos is positive in quadrant I and IV<br>So,&nbsp;<em>x<\/em>&nbsp;= 78\u02da or<br><em>x<\/em>&nbsp;= 360 \u2013 78 = 282\u02da<\/p>\n\n\n\n<p>c) tan&nbsp;<em>x<\/em>&nbsp;= \u20131.4281<\/p>\n\n\n\n<p>reference angle = tan -1 (1.4281)<br>reference angle = 55\u02da (round to the nearest degree)<\/p>\n\n\n\n<p>tan is negative in quadrant II and IV<br>So,&nbsp;<em>x<\/em>&nbsp;= 180 \u2013 55 = 125\u02da or<br><em>x<\/em>&nbsp;= 360 \u2013 55 = 305\u02da<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In these lessons, we will look at Trigonometric Functions for any angle in the Cartesian Plane by using the reference angle. Steps to solving trigonometric functions for any angle Step 1:\u00a0Find the\u00a0Reference Angle, which is always acuteStep 2:\u00a0Find Trig Function Value for the reference angleStep 3:\u00a0Determine the Sign (positive or negative) of the trig function [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[383],"tags":[],"_links":{"self":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/posts\/7667"}],"collection":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/comments?post=7667"}],"version-history":[{"count":0,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/posts\/7667\/revisions"}],"wp:attachment":[{"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/media?parent=7667"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/categories?post=7667"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mudassirbackup.infinitycodestudio.com\/index.php\/wp-json\/wp\/v2\/tags?post=7667"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}