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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

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

B

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

C

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

D

none of these

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The correct Answer is:
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 can follow these steps: ### Step 1: Use the identity for \(\alpha^5 + \beta^5\) We can express \(\alpha^5 + \beta^5\) in terms of \(\alpha^3 + \beta^3\) and \(\alpha^2 + \beta^2\). The identity is: \[ \alpha^5 + \beta^5 = (\alpha + \beta)(\alpha^4 + \beta^4) - \alpha\beta(\alpha^3 + \beta^3) \] We also know that: \[ \alpha^4 + \beta^4 = (\alpha^2 + \beta^2)^2 - 2\alpha^2\beta^2 \] ### 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 and simplify From the given equations, we can substitute the expressions we derived: 1. Substitute \(\alpha^2 + \beta^2 = 5\). 2. Substitute \(\alpha^3 + \beta^3\) into the equation \(3(\alpha^5 + \beta^5) = 11(\alpha^3 + \beta^3)\). This gives us: \[ 3\left((\alpha + \beta)(\alpha^4 + \beta^4) - \alpha\beta(\alpha^3 + \beta^3)\right) = 11(\alpha + \beta)(\alpha^2 + \beta^2 - \alpha\beta) \] ### Step 4: Substitute \(\alpha^4 + \beta^4\) Using the expression for \(\alpha^4 + \beta^4\): \[ \alpha^4 + \beta^4 = 5^2 - 2\alpha^2\beta^2 = 25 - 2\alpha^2\beta^2 \] ### Step 5: Rearranging and solving Substituting everything back into the equation and simplifying will yield a polynomial in terms of \(\alpha + \beta\) and \(\alpha\beta\). Let \(s = \alpha + \beta\) and \(p = \alpha\beta\). The equation simplifies to: \[ 3s(25 - 2p) - 3p\left(s\left(5 - p\right)\right) = 11s(5 - p) \] ### Step 6: Solve for \(p\) After simplifying, we can isolate \(p\) and solve for its value. ### Step 7: Find \(s\) Using the relation \(\alpha^2 + \beta^2 = s^2 - 2p = 5\), we can find \(s\) based on the value of \(p\). ### Step 8: Form the quadratic equation The quadratic equation with roots \(\alpha\) and \(\beta\) is given by: \[ x^2 - sx + p = 0 \] ### Final Result After calculating \(s\) and \(p\), we can write the final quadratic equation.

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 can follow these steps: ### Step 1: Use the identity for \(\alpha^5 + \beta^5\) We can express \(\alpha^5 + \beta^5\) in terms of \(\alpha^3 + \beta^3\) and \(\alpha^2 + \beta^2\). The identity is: \[ \alpha^5 + \beta^5 = (\alpha + \beta)(\alpha^4 + \beta^4) - \alpha\beta(\alpha^3 + \beta^3) ...
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