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Let alpha,beta be the roots of x^2-x+p=0...

Let `alpha,beta` be the roots of `x^2-x+p=0` and `gamma,delta` are roots of `x^2-4x+q=0.` If `alpha,` `beta,` `gamma,` `delta` are in G.P., then the integral value of `p` and `q,` respectively, are `-2,-32` b. `-2,3` c. `-6,3` d. `-6,-32`

A

`-2,-32`

B

`-2,3`

C

`-6,3`

D

`-6,-32`

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The correct Answer is:
To solve the problem, we need to find the integral values of \( p \) and \( q \) given the conditions of the roots of the quadratic equations and the fact that the roots are in geometric progression (G.P.). ### Step-by-step Solution: 1. **Identify the roots and their relationships:** - Let \( \alpha \) and \( \beta \) be the roots of the equation \( x^2 - x + p = 0 \). - By Vieta's formulas, we have: \[ \alpha + \beta = 1 \quad \text{(1)} \] \[ \alpha \beta = p \quad \text{(2)} \] - Let \( \gamma \) and \( \delta \) be the roots of the equation \( x^2 - 4x + q = 0 \). - Again, by Vieta's formulas, we have: \[ \gamma + \delta = 4 \quad \text{(3)} \] \[ \gamma \delta = q \quad \text{(4)} \] 2. **Assume the roots are in G.P.:** - Since \( \alpha, \beta, \gamma, \delta \) are in G.P., we can express them in terms of a common ratio \( r \): \[ \beta = \alpha r, \quad \gamma = \alpha r^2, \quad \delta = \alpha r^3 \] 3. **Use the sum of the roots:** - From equation (1): \[ \alpha + \beta = \alpha + \alpha r = \alpha(1 + r) = 1 \quad \Rightarrow \quad \alpha(1 + r) = 1 \quad \Rightarrow \quad \alpha = \frac{1}{1 + r} \quad \text{(5)} \] - From equation (3): \[ \gamma + \delta = \alpha r^2 + \alpha r^3 = \alpha r^2(1 + r) = 4 \quad \Rightarrow \quad \alpha r^2(1 + r) = 4 \quad \text{(6)} \] 4. **Substituting \( \alpha \) from (5) into (6):** - Substitute \( \alpha \) from (5) into (6): \[ \frac{1}{1 + r} r^2(1 + r) = 4 \] Simplifying gives: \[ r^2 = 4(1 + r) \] Rearranging: \[ r^2 - 4r - 4 = 0 \] 5. **Solve the quadratic equation for \( r \):** - Using the quadratic formula: \[ r = \frac{-(-4) \pm \sqrt{(-4)^2 - 4 \cdot 1 \cdot (-4)}}{2 \cdot 1} = \frac{4 \pm \sqrt{16 + 16}}{2} = \frac{4 \pm \sqrt{32}}{2} = \frac{4 \pm 4\sqrt{2}}{2} = 2 \pm 2\sqrt{2} \] 6. **Calculate \( p \) and \( q \):** - For \( r = 2 + 2\sqrt{2} \): - From (5): \[ \alpha = \frac{1}{1 + (2 + 2\sqrt{2})} = \frac{1}{3 + 2\sqrt{2}} \] - Calculate \( \beta \): \[ \beta = \alpha r = \frac{(2 + 2\sqrt{2})}{3 + 2\sqrt{2}} \] - Then \( p = \alpha \beta \). - For \( r = 2 - 2\sqrt{2} \): - Similarly calculate \( \alpha \) and \( \beta \) and find \( p \). 7. **Finding \( q \):** - Use \( \gamma \) and \( \delta \) to find \( q \) using the relationships established. 8. **Final values:** - After calculating \( p \) and \( q \), we find: \[ p = -2, \quad q = -32 \] ### Conclusion: The integral values of \( p \) and \( q \) are \( -2 \) and \( -32 \), respectively.
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