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The ratio of roots of the equations `ax^(2) + bx + c = 0 and px^(2) + qx + r = 0` are equal If `D_(1) and D_(2)` are respectively discriminants, then what is `(D_(1))/(D_(2))` equal to ?

A

`(a^(2))/(p^(2))`

B

`(b^(2))/(q^(2))`

C

`(c^(2))/(r^(2))`

D

None of these

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The correct Answer is:
To solve the problem, we need to find the ratio of the discriminants of two quadratic equations given that the ratio of their roots is equal. ### Step-by-Step Solution: 1. **Understanding the Quadratic Equations**: We have two quadratic equations: - \( ax^2 + bx + c = 0 \) (Equation 1) - \( px^2 + qx + r = 0 \) (Equation 2) 2. **Roots of the Quadratic Equations**: Let the roots of Equation 1 be \( \alpha \) and \( \beta \), and the roots of Equation 2 be \( \gamma \) and \( \delta \). Given that the ratio of the roots of both equations is equal, we can express this as: \[ \frac{\alpha}{\beta} = \frac{\gamma}{\delta} \] 3. **Using the Relationship of Roots**: For a quadratic equation \( ax^2 + bx + c = 0 \), the sum and product of the roots can be given by: - Sum of roots \( \alpha + \beta = -\frac{b}{a} \) - Product of roots \( \alpha \beta = \frac{c}{a} \) Similarly, for the second equation \( px^2 + qx + r = 0 \): - Sum of roots \( \gamma + \delta = -\frac{q}{p} \) - Product of roots \( \gamma \delta = \frac{r}{p} \) 4. **Finding the Discriminants**: The discriminant \( D \) for a quadratic equation \( ax^2 + bx + c = 0 \) is given by: \[ D = b^2 - 4ac \] Therefore, the discriminants for our equations are: - \( D_1 = b^2 - 4ac \) - \( D_2 = q^2 - 4pr \) 5. **Establishing the Ratio of Discriminants**: From the property of the ratio of the roots, we know that: \[ \frac{\alpha}{\beta} = \frac{\gamma}{\delta} \implies \frac{\alpha}{\beta} = k \text{ (some constant)} \] This leads to the conclusion that: \[ \frac{b^2}{q^2} = \frac{D_1}{D_2} \] Thus, we can express the ratio of the discriminants as: \[ \frac{D_1}{D_2} = \frac{b^2}{q^2} \] 6. **Final Result**: Therefore, the ratio of the discriminants \( \frac{D_1}{D_2} \) is equal to \( \frac{b^2}{q^2} \). ### Conclusion: The final answer is: \[ \frac{D_1}{D_2} = \frac{b^2}{q^2} \]
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