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The ration 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 respective discriminates. 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 \( D_1 \) and \( D_2 \) of the two quadratic equations given that the ratio of their roots is equal. ### Step-by-Step Solution: 1. **Understand the Quadratic Equations**: The two quadratic equations are: \[ ax^2 + bx + c = 0 \quad \text{(1)} \] \[ px^2 + qx + r = 0 \quad \text{(2)} \] 2. **Roots of the Quadratic Equations**: The roots of a quadratic equation \( Ax^2 + Bx + C = 0 \) can be found using the quadratic formula: \[ x = \frac{-B \pm \sqrt{D}}{2A} \] where \( D \) is the discriminant given by: \[ D = B^2 - 4AC \] 3. **Discriminants**: For the first equation (1): \[ D_1 = b^2 - 4ac \] For the second equation (2): \[ D_2 = q^2 - 4pr \] 4. **Ratio of Roots**: The ratio of the roots of the first equation is given by: \[ \text{Ratio}_1 = \frac{-b + \sqrt{D_1}}{-b - \sqrt{D_1}} = \frac{b + \sqrt{D_1}}{b - \sqrt{D_1}} \] The ratio of the roots of the second equation is: \[ \text{Ratio}_2 = \frac{-q + \sqrt{D_2}}{-q - \sqrt{D_2}} = \frac{q + \sqrt{D_2}}{q - \sqrt{D_2}} \] 5. **Setting the Ratios Equal**: Since the problem states that the ratios of the roots are equal, we have: \[ \frac{b + \sqrt{D_1}}{b - \sqrt{D_1}} = \frac{q + \sqrt{D_2}}{q - \sqrt{D_2}} \] 6. **Cross Multiplying**: Cross-multiplying gives us: \[ (b + \sqrt{D_1})(q - \sqrt{D_2}) = (q + \sqrt{D_2})(b - \sqrt{D_1}) \] 7. **Simplifying**: By simplifying the above equation, we can derive a relationship between \( D_1 \) and \( D_2 \). 8. **Finding the Ratio of Discriminants**: After simplification, we find that: \[ \frac{D_1}{D_2} = \frac{b^2}{q^2} \] ### Final Result: Thus, the ratio of the discriminants \( \frac{D_1}{D_2} \) is equal to: \[ \frac{D_1}{D_2} = \frac{b^2}{q^2} \]

To solve the problem, we need to find the ratio of the discriminants \( D_1 \) and \( D_2 \) of the two quadratic equations given that the ratio of their roots is equal. ### Step-by-Step Solution: 1. **Understand the Quadratic Equations**: The two quadratic equations are: \[ ax^2 + bx + c = 0 \quad \text{(1)} ...
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