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Let alpha, beta, gamma be three numbers ...

Let `alpha, beta, gamma` be three numbers such that `(1)/(alpha)+(1)/(beta)+(1)/(gamma)=(1)/(2), (1)/(alpha^(2))+(1)/(beta^(2))+(1)/(gamma^(2))=(9)/(4) and alpha + beta + gamma=2`, then
`{:("Column-I","Column-II"),("(a) " alpha beta gamma ,"(p) " 6),("(b) "Sigma alpha beta, "(q) "8),("(c) "Sigma alpha^(2) , "(r) "-2), ("(d "Sigma alpha^(3),"(s) "-1):}`

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To solve the problem, we are given three conditions involving the numbers \( \alpha, \beta, \gamma \): 1. \( \frac{1}{\alpha} + \frac{1}{\beta} + \frac{1}{\gamma} = \frac{1}{2} \) 2. \( \frac{1}{\alpha^2} + \frac{1}{\beta^2} + \frac{1}{\gamma^2} = \frac{9}{4} \) 3. \( \alpha + \beta + \gamma = 2 \) We need to find the values of \( \alpha \beta \gamma \), \( \sigma \alpha \beta \) (which is \( \alpha \beta + \beta \gamma + \gamma \alpha \)), \( \sigma \alpha^2 \) (which is \( \alpha^2 + \beta^2 + \gamma^2 \)), and \( \sigma \alpha^3 \) (which is \( \alpha^3 + \beta^3 + \gamma^3 \)). ### Step 1: Find \( \alpha \beta \gamma \) From the first condition, we can rewrite it as: \[ \frac{1}{\alpha} + \frac{1}{\beta} + \frac{1}{\gamma} = \frac{\beta \gamma + \alpha \gamma + \alpha \beta}{\alpha \beta \gamma} = \frac{1}{2} \] This implies: \[ \beta \gamma + \alpha \gamma + \alpha \beta = \frac{1}{2} \alpha \beta \gamma \quad \text{(1)} \] ### Step 2: Find \( \frac{1}{\alpha^2} + \frac{1}{\beta^2} + \frac{1}{\gamma^2} \) Using the identity: \[ \frac{1}{\alpha^2} + \frac{1}{\beta^2} + \frac{1}{\gamma^2} = \frac{(\beta \gamma + \alpha \gamma + \alpha \beta)^2 - 2\alpha \beta \gamma(\alpha + \beta + \gamma)}{(\alpha \beta \gamma)^2} \] Substituting the known values: \[ \frac{9}{4} = \frac{(\frac{1}{2} \alpha \beta \gamma)^2 - 2\alpha \beta \gamma \cdot 2}{(\alpha \beta \gamma)^2} \] This leads to: \[ 9(\alpha \beta \gamma)^2 = 4 \left( \frac{1}{4} (\alpha \beta \gamma)^2 - 4 \alpha \beta \gamma \right) \] ### Step 3: Solve for \( \alpha \beta \gamma \) From the above equation, we can simplify and solve for \( \alpha \beta \gamma \): After simplification, we find: \[ \alpha \beta \gamma = -2 \quad \text{(2)} \] ### Step 4: Find \( \sigma \alpha \beta \) Using the relation: \[ \sigma \alpha = \alpha + \beta + \gamma = 2 \] We can substitute this into the equation from step 1 to find \( \sigma \alpha \beta \): \[ \sigma \alpha \beta = \frac{1}{2} \cdot (-2) = -1 \quad \text{(3)} \] ### Step 5: Find \( \sigma \alpha^2 \) Using the identity: \[ \sigma \alpha^2 = (\alpha + \beta + \gamma)^2 - 2\sigma \alpha \beta \] Substituting the known values: \[ \sigma \alpha^2 = 2^2 - 2(-1) = 4 + 2 = 6 \quad \text{(4)} \] ### Step 6: Find \( \sigma \alpha^3 \) Using the identity: \[ \sigma \alpha^3 = (\alpha + \beta + \gamma)(\sigma \alpha^2) - \sigma \alpha \beta \cdot \sigma \alpha \] Substituting the known values: \[ \sigma \alpha^3 = 2 \cdot 6 - (-1)(2) = 12 + 2 = 14 \quad \text{(5)} \] ### Final Results Now we have: - \( \alpha \beta \gamma = -2 \) - \( \sigma \alpha \beta = -1 \) - \( \sigma \alpha^2 = 6 \) - \( \sigma \alpha^3 = 14 \) ### Summary of Results - \( \alpha \beta \gamma = -2 \) (matches option \( r \)) - \( \sigma \alpha \beta = -1 \) (matches option \( s \)) - \( \sigma \alpha^2 = 6 \) (matches option \( p \)) - \( \sigma \alpha^3 = 14 \) (not in options)
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