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Let alpha, beta be two real numbers sati...

Let `alpha`, `beta` be two real numbers satisfying the following relations `alpha^(2)+beta^(2)=5`, `3(alpha^(5)+beta^(5))=11(alpha^(3)+beta^(3))`
Quadratic equation having roots `alpha` and `beta` is

A

(a) `x^(2)+-x+2=0`

B

(b) `x^(2)+-3x-2=0`

C

(c) `x^(2)+-sqrt(3)x+2=0`

D

(d) none of these

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To find the quadratic equation having roots \(\alpha\) and \(\beta\) given the conditions \(\alpha^2 + \beta^2 = 5\) and \(3(\alpha^5 + \beta^5) = 11(\alpha^3 + \beta^3)\), we will follow these steps: ### Step 1: Use the identity for \(\alpha^5 + \beta^5\) We can express \(\alpha^5 + \beta^5\) in terms of lower powers of \(\alpha\) and \(\beta\): \[ \alpha^5 + \beta^5 = (\alpha + \beta)(\alpha^4 + \beta^4) - \alpha\beta(\alpha^3 + \beta^3) \] We also know that: \[ \alpha^4 + \beta^4 = (\alpha^2 + \beta^2)^2 - 2(\alpha\beta)^2 \] ### Step 2: Express \(\alpha^3 + \beta^3\) Using the identity: \[ \alpha^3 + \beta^3 = (\alpha + \beta)(\alpha^2 + \beta^2 - \alpha\beta) \] ### Step 3: Substitute into the given equation Substituting these identities into the equation \(3(\alpha^5 + \beta^5) = 11(\alpha^3 + \beta^3)\): \[ 3[(\alpha + \beta)(\alpha^4 + \beta^4) - \alpha\beta(\alpha^3 + \beta^3)] = 11(\alpha + \beta)(\alpha^2 + \beta^2 - \alpha\beta) \] ### Step 4: Let \(\alpha + \beta = s\) and \(\alpha\beta = p\) Now, let \(s = \alpha + \beta\) and \(p = \alpha\beta\). We can rewrite our equations: 1. From \(\alpha^2 + \beta^2 = 5\): \[ s^2 - 2p = 5 \quad \Rightarrow \quad s^2 = 5 + 2p \] 2. Substitute \(s\) and \(p\) into the equation: \[ 3[s((5 + 2p) - p)] - 3p\left[s\left(\frac{s^2 - p}{s}\right)\right] = 11s\left(5 - p\right) \] ### Step 5: Simplify the equation After simplifying, we will arrive at a quadratic equation in terms of \(p\): \[ 3s(5 + p) - 3ps = 11s(5 - p) \] This simplifies to: \[ 15s + 3sp - 3ps = 55s - 11sp \] Rearranging gives: \[ (3 + 11)p = 55 - 15 \] Thus, we can solve for \(p\). ### Step 6: Solve for \(p\) From the rearranged equation, we find: \[ 14p = 40 \quad \Rightarrow \quad p = \frac{40}{14} = \frac{20}{7} \] ### Step 7: Find \(s\) Substituting \(p\) back into the equation for \(s\): \[ s^2 = 5 + 2\left(\frac{20}{7}\right) = 5 + \frac{40}{7} = \frac{35 + 40}{7} = \frac{75}{7} \] Thus, \[ s = \pm \sqrt{\frac{75}{7}} = \pm \frac{5\sqrt{3}}{7} \] ### Step 8: Form the quadratic equation The quadratic equation with roots \(\alpha\) and \(\beta\) is given by: \[ x^2 - sx + p = 0 \] Substituting \(s\) and \(p\): \[ x^2 - \left(\pm \frac{5\sqrt{3}}{7}\right)x + \frac{20}{7} = 0 \] ### Final Quadratic Equation Thus, the quadratic equation having roots \(\alpha\) and \(\beta\) is: \[ 7x^2 \mp 5\sqrt{3}x + 20 = 0 \]

To find the quadratic equation having roots \(\alpha\) and \(\beta\) given the conditions \(\alpha^2 + \beta^2 = 5\) and \(3(\alpha^5 + \beta^5) = 11(\alpha^3 + \beta^3)\), we will follow these steps: ### Step 1: Use the identity for \(\alpha^5 + \beta^5\) We can express \(\alpha^5 + \beta^5\) in terms of lower powers of \(\alpha\) and \(\beta\): \[ \alpha^5 + \beta^5 = (\alpha + \beta)(\alpha^4 + \beta^4) - \alpha\beta(\alpha^3 + \beta^3) \] We also know that: ...
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