Given the equation \( 5\sin(x) - 12\cos(x) = 0 \), use the auxiliary angle method to find all possible values of x within one period.
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To solve the equation \( 5\sin(x) - 12\cos(x) = 0 \) using the auxiliary angle method, we can rewrite it in the form \( R\sin(x + \phi) = 0 \). First, we need to express the equation in terms of sine and cosine. We rearrange it to: \[ 5\sin(x) = 12\cos(x) \] Dividing both sides by \( \cos(x) \) (assuming \( \cos(x) \neq 0 \)), we get: \[ \tan(x) = \frac{12}{5} \] Using the auxiliary angle, we write the equation as: \[ R\sin(x + \phi) = 0 \] where \( R = \sqrt{5^2 + 12^2} = \sqrt{25 + 144} = \sqrt{169} = 13 \). Next, we find the angle \( \phi \) such that: \[ \cos(\phi) = \frac{12}{13}, \quad \sin(\phi) = \frac{5}{13} \] Thus, \( \phi = \tan^{-1}\left(\frac{5}{12}\right) \). Now we set up the equation: \[ \sin(x + \phi) = 0 \] This gives us: \[ x + \phi = n\pi \quad (n \in \mathbb{Z}) \] Solving for \( x \): \[ x = n\pi - \phi \] Since we want values of \( x \) within one period (i.e., \( [0, 2\pi) \)), we consider \( n = 0 \) and \( n = 1 \): 1. For \( n = 0 \): \[ x = -\phi \quad \text{(not in } [0, 2\pi) \text{, so we discard)} \] 2. For \( n = 1 \): \[ x = \pi - \phi \] 3. For \( n = 2 \): \[ x = 2\pi - \phi \] Now, substituting \( \phi \): 1. \( x_1 = \pi - \tan^{-1}\left(\frac{5}{12}\right) \) 2. \( x_2 = 2\pi - \tan^{-1}\left(\frac{5}{12}\right) \) To evaluate numerically (using \( \tan^{-1}\left(\frac{5}{12}\right) \approx 0.39479 \) radians): 1. \( x_1 \approx \pi - 0.39479 \approx 2.74680 \) 2. \( x_2 \approx 2\pi - 0.39479 \approx 5.88834 \) Thus, the possible values of \( x \) within one period \( [0, 2\pi) \) are: \[ x \approx 2.74680 \quad \text{and} \quad x \approx 5.88834 \]