A Nice Equation - Cosine Double and Triple Angles

Explore a fascinating mathematical problem involving cosine double and triple angles in this 12-minute video. Learn three distinct methods to solve the equation, starting with the problem introduction at 0:00, followed by method 1 at 1:07, method 2 at 7:03, and method 3 at 9:44. Discover various approaches to tackle this intriguing equation originally posted on Reddit AskMath, enhancing your understanding of trigonometric identities and problem-solving techniques.

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