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Let `alpha,beta in Rdot` If `alpha,beta^2` are the roots of quadratic equation `x^2-p x+1=0a n dalpha^2,beta` is the roots of quadratic equation `x^2-q x+8=0` , then the value of `rifr/8` is the arithmetic mean of `p a n d q ,` is

A

`83/2`

B

83

C

`83/8`

D

`83/4`

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To solve the problem step by step, we will analyze the given quadratic equations and use the properties of roots. ### Step 1: Identify the roots and their relationships We have two quadratic equations: 1. \( x^2 - px + 1 = 0 \) with roots \( \alpha \) and \( \beta^2 \) 2. \( x^2 - qx + 8 = 0 \) with roots \( \alpha^2 \) and \( \beta \) ### Step 2: Use the product of roots For the first equation: - The product of the roots \( \alpha \cdot \beta^2 = 1 \) (Equation 1). For the second equation: - The product of the roots \( \alpha^2 \cdot \beta = 8 \) (Equation 2). ### Step 3: Multiply the two equations From Equation 1 and Equation 2: \[ (\alpha \cdot \beta^2) \cdot (\alpha^2 \cdot \beta) = 1 \cdot 8 \] This simplifies to: \[ \alpha^3 \cdot \beta^3 = 8 \] Taking the cube root of both sides: \[ \alpha \cdot \beta = 2 \quad \text{(Equation 3)} \] ### Step 4: Express beta in terms of alpha From Equation 1: \[ \alpha \cdot \beta^2 = 1 \implies \beta^2 = \frac{1}{\alpha} \implies \beta = \sqrt{\frac{1}{\alpha}} = \frac{1}{\sqrt{\alpha}} \quad \text{(Equation 4)} \] ### Step 5: Substitute beta in Equation 3 Substituting Equation 4 into Equation 3: \[ \alpha \cdot \frac{1}{\sqrt{\alpha}} = 2 \] This simplifies to: \[ \sqrt{\alpha} = 2 \implies \alpha = 4 \] ### Step 6: Find beta Using the value of \( \alpha \) in Equation 4: \[ \beta = \frac{1}{\sqrt{4}} = \frac{1}{2} \] ### Step 7: Calculate p and q Now we can find \( p \) and \( q \). For \( p \): \[ p = \alpha + \beta^2 = 4 + \left(\frac{1}{2}\right)^2 = 4 + \frac{1}{4} = \frac{16}{4} + \frac{1}{4} = \frac{17}{4} \quad \text{(Equation 5)} \] For \( q \): \[ q = \alpha^2 + \beta = 4^2 + \frac{1}{2} = 16 + \frac{1}{2} = 16 + \frac{1}{2} = \frac{32}{2} + \frac{1}{2} = \frac{33}{2} \quad \text{(Equation 6)} \] ### Step 8: Find R We know that \( \frac{R}{8} \) is the arithmetic mean of \( p \) and \( q \): \[ \frac{R}{8} = \frac{p + q}{2} \] Substituting the values of \( p \) and \( q \): \[ \frac{R}{8} = \frac{\frac{17}{4} + \frac{33}{2}}{2} \] Finding a common denominator (which is 4): \[ \frac{R}{8} = \frac{\frac{17}{4} + \frac{66}{4}}{2} = \frac{\frac{83}{4}}{2} = \frac{83}{8} \] Thus: \[ R = 83 \] ### Final Answer The value of \( R \) is \( 83 \). ---

To solve the problem step by step, we will analyze the given quadratic equations and use the properties of roots. ### Step 1: Identify the roots and their relationships We have two quadratic equations: 1. \( x^2 - px + 1 = 0 \) with roots \( \alpha \) and \( \beta^2 \) 2. \( x^2 - qx + 8 = 0 \) with roots \( \alpha^2 \) and \( \beta \) ### Step 2: Use the product of roots ...
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