{"id":1289,"date":"2023-09-27T14:16:35","date_gmt":"2023-09-27T14:16:35","guid":{"rendered":"http:\/\/localhost\/ecole9ja\/?p=1289"},"modified":"2023-09-27T14:18:35","modified_gmt":"2023-09-27T14:18:35","slug":"week-4-jss-2-third-term-mathematics-lesson-notes","status":"publish","type":"post","link":"https:\/\/ecolebooks.com\/nigeria\/posts\/week-4-jss-2-third-term-mathematics-lesson-notes\/","title":{"rendered":"Week 4 – Jss 2 Third Term Mathematics Lesson Notes"},"content":{"rendered":"

WEEK 4\u00a0\u00a0\u00a0\u00a0ANGLES OF ELEVATION AND DEPRESSION
\n<\/strong>
\n\u00a0What is angle of elevation?<\/strong>The angle of elevation <\/strong>is the angle between a horizontal line from the observer and the line of sight to an object that is above the horizontal line.
\n\"\"\/\"\"\/In the diagram below, AB<\/em> is the horizontal line. q<\/em> is the angle of elevation from the observer at A<\/em> to the object at C<\/em>. <\/p>\n

\u00a0
\n\u00a0
\n\u00a0\"\"\/\"\"\/
\n\t\t A B
\nWhat is angle of depression?<\/strong>The angle of depression <\/strong>is the angle between a horizontal line from the observer and the line of sight to an object that is below the horizontal line.
\nIn the diagram below, PQ<\/em> is the horizontal line. q<\/em> is the angle of depression from the observer at P<\/em> to the object at R<\/em>.
\n\"\"\/\"\"\/\"\"\/\"\"\/<\/p>\n

\u00a0
\n\u00a0
\n\u00a0
\n\u00a0\"\"\/
\n\t\t\t<\/em>\u00a0
\n\u00a0How to solve word problems that involves angle of elevation or depression?<\/strong>Step 1: Draw a sketch of the situation.Step 2: Mark in the given angle of elevation or depression.Step 3: Use trigonometry to find the required missing length
\nExample: <\/em>
\n\t\tTwo poles on horizontal ground are 60 m apart. The shorter pole is 3 m high. The angle of depression of the top of the shorter pole from the top of the longer pole is 20\u02da. Sketch a diagram to represent the situation.
\nSolution: <\/em><\/p>\n

\u00a0Step 1<\/strong>: Draw two vertical lines to represent the shorter pole and the longer pole.
\nStep 2<\/strong>: Draw a line from the top of the longer pole to the top of the shorter pole. (This is the line of sight).
\n\"\"\/
\n\t\tStep 3: Draw a horizontal line to the top of the pole and mark in the angle of depression.
\n\"\"\/
\n\t\tExample: <\/em>
\n\t\tA man who is 2 m tall stands on horizontal ground 30 m from a tree. The angle of elevation of the top of the tree from his eyes is 28\u02da. Estimate the height of the tree.
\nSolution:<\/em>
\n\t\tLet the height of the tree be h<\/em>. Sketch a diagram to represent the situation.
\n\"\"\/
\n\t\ttan 28\u02da = \"\"\/
\n\t\th<\/em> \u2013 2 = 30 tan 28\u02da
\nh <\/em>= (30 \u00b4 0.5317) + 2 \u2190 tan 28\u02da = 0.5317
\n= 17.951
\nThe height of the tree is approximately 17.95 m<\/strong>.
\n\t\t\t\t<\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

WEEK 4\u00a0\u00a0\u00a0\u00a0ANGLES OF ELEVATION AND DEPRESSION \u00a0What is angle of elevation?The angle of elevation is…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1,123],"tags":[],"class_list":["post-1289","post","type-post","status-publish","format-standard","hentry","category-posts","category-third-term-jss2-mathematics"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts\/1289","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/comments?post=1289"}],"version-history":[{"count":1,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts\/1289\/revisions"}],"predecessor-version":[{"id":1290,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/posts\/1289\/revisions\/1290"}],"wp:attachment":[{"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/media?parent=1289"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/categories?post=1289"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ecolebooks.com\/nigeria\/wp-json\/wp\/v2\/tags?post=1289"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}