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If ( sin ^(3) theta)/( sin ( 2theta+ alp...

If `( sin ^(3) theta)/( sin ( 2theta+ alpha )) = ( cos ^(3) theta)/( cos ( 2 theta + alpha)) and tan 2 theta = lamda tan ( 3theta + alpha)` then the value of `lamda` is ____________.

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To solve the problem, we start with the given equations: 1. \(\frac{\sin^3 \theta}{\sin(2\theta + \alpha)} = \frac{\cos^3 \theta}{\cos(2\theta + \alpha)}\) 2. \(\tan(2\theta) = \lambda \tan(3\theta + \alpha)\) We need to find the value of \(\lambda\). ### Step 1: Cross-multiply the first equation Cross-multiplying the first equation gives us: \[ \sin^3 \theta \cdot \cos(2\theta + \alpha) = \cos^3 \theta \cdot \sin(2\theta + \alpha) \] ### Step 2: Rewrite the equation We can rewrite this as: \[ \sin^3 \theta \cdot \cos(2\theta + \alpha) - \cos^3 \theta \cdot \sin(2\theta + \alpha) = 0 \] ### Step 3: Factor the equation This can be factored using the identity \(a^3 - b^3 = (a - b)(a^2 + ab + b^2)\): \[ (\sin \theta - \cos \theta)(\sin^2 \theta + \sin \theta \cos \theta + \cos^2 \theta) = 0 \] ### Step 4: Analyze the factors Since \(\sin^2 \theta + \sin \theta \cos \theta + \cos^2 \theta\) is always positive, we focus on: \[ \sin \theta - \cos \theta = 0 \implies \sin \theta = \cos \theta \implies \theta = \frac{\pi}{4} + n\pi \] ### Step 5: Substitute \(\theta\) into the second equation Now, substituting \(\theta = \frac{\pi}{4}\) into the second equation: \[ \tan(2\cdot\frac{\pi}{4}) = \lambda \tan(3\cdot\frac{\pi}{4} + \alpha) \] This simplifies to: \[ \tan(\frac{\pi}{2}) = \lambda \tan(\frac{3\pi}{4} + \alpha) \] Since \(\tan(\frac{\pi}{2})\) is undefined, we need to analyze the right side. ### Step 6: Analyze the right side The value of \(\tan(\frac{3\pi}{4} + \alpha)\) can be expressed as: \[ \tan(\frac{3\pi}{4}) = -1 \implies \tan(\frac{3\pi}{4} + \alpha) = \frac{-1 + \tan \alpha}{1 - (-1)\tan \alpha} = \frac{-1 + \tan \alpha}{1 + \tan \alpha} \] ### Step 7: Set up the equation Thus, we have: \[ \text{undefined} = \lambda \cdot \frac{-1 + \tan \alpha}{1 + \tan \alpha} \] For the left side to be undefined, the right side must also be undefined, which occurs when: \[ 1 + \tan \alpha = 0 \implies \tan \alpha = -1 \implies \alpha = \frac{3\pi}{4} + n\pi \] ### Step 8: Substitute back to find \(\lambda\) We can now substitute back to find \(\lambda\): \[ \tan(2\theta) = \lambda \tan(3\theta + \alpha) \implies 2 = \lambda \cdot (-1) \] Thus, we find: \[ \lambda = -2 \] ### Final Answer The value of \(\lambda\) is: \[ \lambda = 2 \]

To solve the problem, we start with the given equations: 1. \(\frac{\sin^3 \theta}{\sin(2\theta + \alpha)} = \frac{\cos^3 \theta}{\cos(2\theta + \alpha)}\) 2. \(\tan(2\theta) = \lambda \tan(3\theta + \alpha)\) We need to find the value of \(\lambda\). ### Step 1: Cross-multiply the first equation ...
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