{"id":193805,"date":"2025-02-21T04:48:19","date_gmt":"2025-02-21T04:48:19","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=193805"},"modified":"2025-02-21T04:48:21","modified_gmt":"2025-02-21T04:48:21","slug":"sin-3pi-2-3pi-4-can-be-expanded-to","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/02\/21\/sin-3pi-2-3pi-4-can-be-expanded-to\/","title":{"rendered":"sin (3pi\/2 &#8211; 3pi\/4) can be expanded to"},"content":{"rendered":"\n<p>A. sin (3pi\/2 &#8211; 3pi\/4) can be expanded to:<\/p>\n\n\n\n<p>A. cos 3pi\/2 cos 3pi\/4 + sin 3pi\/2 cos 3pi\/4<\/p>\n\n\n\n<p>B. sin 3pi\/2 cos 3pi\/4 &#8211; cos 3pi\/2 sin 3pi\/4<\/p>\n\n\n\n<p>C. cos 3pi\/2 cos 3pi\/4 &#8211; sin 3pi\/2 sin 3pi\/4<\/p>\n\n\n\n<p>D. sin 3pi\/2 cos 3pi\/4 + cos 3pi\/2 sin 3pi\/4<\/p>\n\n\n\n<p>B. Thick expression is obtained on subtracting 4x+6 from 7+2x?<\/p>\n\n\n\n<p><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-6-color\"><strong>The Correct Answer and Explanation is :<\/strong><\/mark><\/p>\n\n\n\n<p>Let&#8217;s solve each part of your query one at a time.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Part A: Trigonometry Problem<\/h3>\n\n\n\n<p>You are asked to expand the expression (\\sin \\left(\\frac{3\\pi}{2} &#8211; \\frac{3\\pi}{4}\\right)) using the angle subtraction formula for sine, which is:<\/p>\n\n\n\n<p>[<br>\\sin(a &#8211; b) = \\sin a \\cos b &#8211; \\cos a \\sin b<br>]<\/p>\n\n\n\n<p>Plugging in the values (a = \\frac{3\\pi}{2}) and (b = \\frac{3\\pi}{4}), we have:<\/p>\n\n\n\n<p>[<br>\\sin \\left(\\frac{3\\pi}{2} &#8211; \\frac{3\\pi}{4}\\right) = \\sin \\frac{3\\pi}{2} \\cos \\frac{3\\pi}{4} &#8211; \\cos \\frac{3\\pi}{2} \\sin \\frac{3\\pi}{4}<br>]<\/p>\n\n\n\n<p>To evaluate this, remember the values of sine and cosine at these specific angles:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>(\\sin \\frac{3\\pi}{2} = -1)<\/li>\n\n\n\n<li>(\\cos \\frac{3\\pi}{2} = 0)<\/li>\n\n\n\n<li>(\\sin \\frac{3\\pi}{4} = \\frac{\\sqrt{2}}{2})<\/li>\n\n\n\n<li>(\\cos \\frac{3\\pi}{4} = -\\frac{\\sqrt{2}}{2})<\/li>\n<\/ul>\n\n\n\n<p>Substituting these into the formula gives:<\/p>\n\n\n\n<p>[<br>(-1)(-\\frac{\\sqrt{2}}{2}) &#8211; (0)(\\frac{\\sqrt{2}}{2}) = \\frac{\\sqrt{2}}{2}<br>]<\/p>\n\n\n\n<p>This matches the expansion:<br>[<br>\\sin \\frac{3\\pi}{2} \\cos \\frac{3\\pi}{4} + \\cos \\frac{3\\pi}{2} \\sin \\frac{3\\pi}{4}<br>]<\/p>\n\n\n\n<p>So, the correct option is <strong>D.<\/strong><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Part B: Algebra Problem<\/h3>\n\n\n\n<p>The expression for subtracting (4x + 6) from (7 + 2x) is calculated as follows:<\/p>\n\n\n\n<p>[<br>(7 + 2x) &#8211; (4x + 6)<br>]<\/p>\n\n\n\n<p>Distribute the negative sign through the second term:<br>[<br>7 + 2x &#8211; 4x &#8211; 6<br>]<\/p>\n\n\n\n<p>Combine like terms:<br>[<br>1 &#8211; 2x<br>]<\/p>\n\n\n\n<p>This represents the result of the subtraction: &#8220;1 &#8211; 2x.&#8221; This result is simply obtained by direct subtraction and combining like terms. The subtraction involves distributing the minus sign across (4x + 6) and then consolidating the x terms and the constant terms independently.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Generating the Image<\/h3>\n\n\n\n<p>Now let&#8217;s create an image that visually represents the algebraic expression subtraction process:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Image Description:<\/strong> A chalkboard with the algebraic expression (7 + 2x &#8211; (4x + 6)) written in white chalk, showing each step of the subtraction: distribution of the negative sign, combining like terms, and resulting in (1 &#8211; 2x). Include visual arrows and annotations explaining each step.<\/li>\n<\/ul>\n\n\n\n<p>I&#8217;ll generate this image now.<\/p>\n\n\n\n<p>Here&#8217;s the image representing the step-by-step subtraction of the algebraic expression (7 + 2x &#8211; (4x + 6)). Each step is clearly annotated to show how the terms are combined to arrive at the final expression (1 &#8211; 2x). You can view the visual explanation on the chalkboard in the image above.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/02\/image-1132.png\" alt=\"\" class=\"wp-image-193806\"\/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>A. sin (3pi\/2 &#8211; 3pi\/4) can be expanded to: A. cos 3pi\/2 cos 3pi\/4 + sin 3pi\/2 cos 3pi\/4 B. sin 3pi\/2 cos 3pi\/4 &#8211; cos 3pi\/2 sin 3pi\/4 C. cos 3pi\/2 cos 3pi\/4 &#8211; sin 3pi\/2 sin 3pi\/4 D. sin 3pi\/2 cos 3pi\/4 + cos 3pi\/2 sin 3pi\/4 B. Thick expression is obtained on [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-193805","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/193805","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=193805"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/193805\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=193805"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=193805"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=193805"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}