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If alpha and beta are non-zero real numb...

If `alpha and beta` are non-zero real number such that `2(cos beta-cos alpha)+cos alpha cos beta=1.` Then which of the following is treu?

A

`tan ((alpha )/(2)) + sqrt3 tan ((beta)/(2)) =0`

B

`sqrt3 tan ((alpha)/(2)) + tan ((beta)/(2)) =0`

C

`tan ((alpha )/(2)) - sqrt3 tan ((beta)/(2)) =0`

D

`sqrt3 tan (( alpha )/(2)) - tan ((beta)/(2))= 0`

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To solve the equation \( 2(\cos \beta - \cos \alpha) + \cos \alpha \cos \beta = 1 \), we will follow these steps: ### Step 1: Rewrite the equation Start with the given equation: \[ 2(\cos \beta - \cos \alpha) + \cos \alpha \cos \beta = 1 \] This can be rewritten as: \[ 2\cos \beta - 2\cos \alpha + \cos \alpha \cos \beta = 1 \] ### Step 2: Rearranging the equation Rearranging gives: \[ 2\cos \beta + \cos \alpha \cos \beta - 2\cos \alpha = 1 \] ### Step 3: Multiply through by 2 To eliminate fractions, multiply the entire equation by 2: \[ 4\cos \beta + 2\cos \alpha \cos \beta - 4\cos \alpha = 2 \] ### Step 4: Group terms Now, group the terms: \[ (4\cos \beta + 2\cos \alpha \cos \beta) - 4\cos \alpha = 2 \] ### Step 5: Factor out common terms Factor out \( \cos \beta \): \[ \cos \beta(4 + 2\cos \alpha) - 4\cos \alpha = 2 \] ### Step 6: Isolate \( \cos \beta \) Rearranging gives: \[ \cos \beta(4 + 2\cos \alpha) = 2 + 4\cos \alpha \] Thus, \[ \cos \beta = \frac{2 + 4\cos \alpha}{4 + 2\cos \alpha} \] ### Step 7: Simplifying the expression Now simplify the expression: \[ \cos \beta = \frac{2(1 + 2\cos \alpha)}{2(2 + \cos \alpha)} = \frac{1 + 2\cos \alpha}{2 + \cos \alpha} \] ### Step 8: Use trigonometric identities Using the half-angle identities: \[ 1 - \cos \alpha = 2\sin^2\left(\frac{\alpha}{2}\right) \quad \text{and} \quad 1 - \cos \beta = 2\sin^2\left(\frac{\beta}{2}\right) \] We can rewrite: \[ \frac{1 - \cos \alpha}{1 + \cos \alpha} = \tan^2\left(\frac{\alpha}{2}\right) \] and \[ \frac{1 - \cos \beta}{1 + \cos \beta} = \tan^2\left(\frac{\beta}{2}\right) \] ### Step 9: Setting up the final equation Thus, we have: \[ \frac{1 - \cos \alpha}{1 + \cos \alpha} = 3 \cdot \frac{1 - \cos \beta}{1 + \cos \beta} \] This leads to: \[ \tan^2\left(\frac{\alpha}{2}\right) = 3 \tan^2\left(\frac{\beta}{2}\right) \] ### Step 10: Final results From this, we can conclude: \[ \tan\left(\frac{\alpha}{2}\right) = \pm \sqrt{3} \tan\left(\frac{\beta}{2}\right) \] ### Summary The derived relationships indicate that: 1. \( \tan\left(\frac{\alpha}{2}\right) + \sqrt{3} \tan\left(\frac{\beta}{2}\right) = 0 \) 2. \( \tan\left(\frac{\alpha}{2}\right) - \sqrt{3} \tan\left(\frac{\beta}{2}\right) = 0 \)

To solve the equation \( 2(\cos \beta - \cos \alpha) + \cos \alpha \cos \beta = 1 \), we will follow these steps: ### Step 1: Rewrite the equation Start with the given equation: \[ 2(\cos \beta - \cos \alpha) + \cos \alpha \cos \beta = 1 \] This can be rewritten as: ...
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