Normal 0false false falseEN-IN X-NONE X-NONEMicrosoftInternetExplorer4/* Style Definitions */table.MsoNormalTable{mso-style-name:Table Normal;mso-tstyle-rowband-size:0;mso-tstyle-colband-size:0;mso-style-noshow:yes;mso-style-priority:99;mso-style-qformat:yes;mso-style-parent:;mso-padding-alt:0cm 5.4pt 0cm 5.4pt;mso-para-margin-top:0cm;mso-para-margin-right:0cm;mso-para-margin-bottom:10.0pt;mso-para-margin-left:0cm;text-align:justify;line-height:12.0pt;mso-line-height-rule:exactly;mso-pagination:widow-orphan;font-size:11.0pt;font-family:Calibri,sans-serif;mso-ascii-font-family:Calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Times New Roman;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:Calibri;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:Times New Roman;mso-bidi-theme-font:minor-bidi;}If Sin a+ sin2a=1 then,find the value of cos12 a +3cos 10a+3cos 8a+cos 6a-1
neet kavya , 13 Years ago
Grade 11
1 Answers
Pramod J AskiitiansExpert-IIT-B
Last Activity: 13 Years ago
Dear student,
cos12 a +3cos 10a+3cos 8a+cos 6a-1
can be written as [cos^2 a + cos^4 a]^3 - 1
from given equation sin^2 a = 1 - sin a => cos^2 a = sin a
=> [ sina a + sin^2 a ]^3 - 1
=> 1^3 - 1
=> 0
hope it explains !!
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