Question:medium

$cos 20^{\circ} + cos 80^{\circ} - \sqrt{3} cos 50^{\circ} =$

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Look for angles that sum or subtract to standard values ($30^{\circ}, 45^{\circ}, 60^{\circ}$) when using transformation formulas.

Updated On: Jul 4, 2026

-1
0
1
$\sqrt{3}$

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The Correct Option is B

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