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Consider the following for the next two ...

Consider the following for the next two items that follow :
`2x^(2) + 3x - alpha = 0` has roots - 2 and `beta` while the equation `x^(2) - 3mx + 2m^(2) = 0` has both roots positive, where `alpha gt 0 and beta gt 0` .
If `beta.2.2m` are in GP. Then what is the value of `beta sqrt(m)`

A

1

B

2

C

4

D

6

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The correct Answer is:
To solve the problem step by step, we will follow the given information and derive the necessary values. ### Step 1: Find the value of alpha We are given the quadratic equation: \[ 2x^2 + 3x - \alpha = 0 \] with roots -2 and β. According to Vieta's formulas, the sum of the roots (−2 + β) is equal to \(-\frac{b}{a}\) and the product of the roots (−2 * β) is equal to \(\frac{c}{a}\). From the equation: - The sum of the roots: \[ -2 + \beta = -\frac{3}{2} \] This simplifies to: \[ \beta = -\frac{3}{2} + 2 = \frac{1}{2} \] - The product of the roots: \[ (-2) \cdot \beta = \frac{-\alpha}{2} \] Substituting \(\beta = \frac{1}{2}\): \[ -2 \cdot \frac{1}{2} = \frac{-\alpha}{2} \] This simplifies to: \[ -1 = \frac{-\alpha}{2} \implies \alpha = 2 \] ### Step 2: Substitute alpha back into the equation Now we have: \[ 2x^2 + 3x - 2 = 0 \] ### Step 3: Find the roots of the equation We will solve the quadratic equation \(2x^2 + 3x - 2 = 0\) using the factorization method: \[ 2x^2 + 4x - x - 2 = 0 \] Grouping the terms: \[ (2x^2 + 4x) + (-x - 2) = 0 \] Factoring out: \[ 2x(x + 2) - 1(x + 2) = 0 \] This gives: \[ (2x - 1)(x + 2) = 0 \] Thus, the roots are: \[ x = \frac{1}{2} \quad \text{and} \quad x = -2 \] So, \(\beta = \frac{1}{2}\). ### Step 4: Analyze the second quadratic equation The second equation is: \[ x^2 - 3mx + 2m^2 = 0 \] We know both roots are positive. According to Vieta's formulas: - The sum of the roots is \(3m\) (which must be positive). - The product of the roots is \(2m^2\) (which must also be positive). ### Step 5: Determine the condition for GP We are given that \(\beta\), 2, and \(2m\) are in geometric progression (GP). In a GP, the square of the middle term is equal to the product of the other two terms: \[ 2^2 = \beta \cdot 2m \] Substituting \(\beta = \frac{1}{2}\): \[ 4 = \frac{1}{2} \cdot 2m \] This simplifies to: \[ 4 = m \] ### Step 6: Calculate \(\beta \sqrt{m}\) Now we need to find \(\beta \sqrt{m}\): \[ \beta = \frac{1}{2}, \quad m = 4 \implies \sqrt{m} = \sqrt{4} = 2 \] Thus: \[ \beta \sqrt{m} = \frac{1}{2} \cdot 2 = 1 \] ### Final Answer The value of \(\beta \sqrt{m}\) is \(1\). ---
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