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What is cos 20 + cos 40 + ... + cos 160 + cos 180.

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Student

High School - 11th Grade

Topic: Math

Posted by fiona1112 on November 9, 2011 at 11:04 PM via web and tagged with math, trigonometry

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College - Senior

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We have to determine the value of cos 20 + cos 40 + ... + cos 160 + cos 180

Use the property cos...

(The entire answer is 68 words.)

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Posted by justaguide on November 9, 2011 at 11:43 PM (Answer #2)

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