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Triple Cosines

Geometry Level 2

Find the value of \(\cos(42^\circ)+\cos(78^\circ)+\cos(162^\circ) \).

0 1 -1 -2

Excel in math and science

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It's hard to learn from lectures and videos

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including olympiad champions, researchers, and professionals.

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View solutions

by Kutumbaka Jaswanth

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