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Задача Задача №2611393
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Аноним
10 января 2025 14:37 · публичный вопрос
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Аноним

решите уравнение

Ответ нейросети
10 января 2025 14:37

To solve the equation \( \sin 3x = \cos 2x \), we'll use trigonometric identities.

We know that: \[ \sin 3x = \sin(2x + x) = \sin 2x \cos x + \cos 2x \sin x \] \[ \cos 2x = \cos^2 x - \sin^2 x \]

Thus, the equation becomes: \[ \sin 2x \cos x + \cos 2x \sin x = \cos 2x \]

Substituting for \(\sin 2x\) and \(\cos 2x\): \[ 2\sin x \cos x \cos x + (\cos^2 x - \sin^2 x) \sin x = \cos^2 x - \sin^2 x \]

To solve:

  1. Simplify and factor: \[ 2\sin x \cos^2 x + \sin x \cos^2 x - \sin^3 x = \cos^2 x - \sin^2 x \]

  2. After simplifying and rearranging terms, use identities and algebra to solve for \(x\).

Alternatively, solve \(\tan 3x = 2\) directly or evaluate the initial equation for specific angle multiples since \(\tan(x) = \tan(\pi + x)\).

Final solution requires specific calculation or graphing to find \(x\) such that \(3x\) and \(2x\) satisfy the angle condition for tangent equivalence.