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If alpha , beta are the roots of ax^2 + ...

If `alpha , beta` are the roots of `ax^2 + bx + c = 0; alpha + h, beta + h` are the roots of `px^2 + gx + r =0` and `D_1, D_2` the respective discriminants of these equations, then `D_1 : D_2 =`

A

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

B

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

C

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

D

none of these

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To solve the problem, we need to find the ratio of the discriminants \( D_1 : D_2 \) for the given quadratic equations. Let's break down the solution step by step. ### Step 1: Identify the roots and their relationships Let \( \alpha \) and \( \beta \) be the roots of the equation \( ax^2 + bx + c = 0 \). According to Vieta's formulas: - The sum of the roots \( \alpha + \beta = -\frac{b}{a} \) - The product of the roots \( \alpha \beta = \frac{c}{a} \) Now, the roots of the second equation \( px^2 + gx + r = 0 \) are \( \alpha + h \) and \( \beta + h \). ### Step 2: Find the sum and product of the new roots The sum of the new roots is: \[ (\alpha + h) + (\beta + h) = \alpha + \beta + 2h = -\frac{b}{a} + 2h \] The product of the new roots is: \[ (\alpha + h)(\beta + h) = \alpha \beta + h(\alpha + \beta) + h^2 = \frac{c}{a} + h\left(-\frac{b}{a}\right) + h^2 \] Thus, we can express the sum and product of the new roots in terms of \( p, g, r \): - Sum: \( -\frac{g}{p} = -\frac{b}{a} + 2h \) - Product: \( \frac{r}{p} = \frac{c}{a} - \frac{bh}{a} + h^2 \) ### Step 3: Write the discriminants The discriminant \( D_1 \) of the first equation is given by: \[ D_1 = b^2 - 4ac \] The discriminant \( D_2 \) of the second equation can be expressed as: \[ D_2 = g^2 - 4pr \] ### Step 4: Substitute the values of \( g \) and \( r \) From the relationships we derived: - \( g = p\left(-\frac{b}{a} + 2h\right) \) - \( r = p\left(\frac{c}{a} - \frac{bh}{a} + h^2\right) \) Substituting these into \( D_2 \): \[ D_2 = \left(p\left(-\frac{b}{a} + 2h\right)\right)^2 - 4p\left(\frac{c}{a} - \frac{bh}{a} + h^2\right) \] ### Step 5: Simplify the discriminants After substituting and simplifying, we find: \[ D_2 = \frac{q^2 - 4rp}{p^2} \] where \( q \) and \( r \) are derived from the new roots. ### Step 6: Establish the ratio of the discriminants From the expressions for \( D_1 \) and \( D_2 \), we can establish the ratio: \[ \frac{D_1}{D_2} = \frac{a^2}{p^2} \] ### Conclusion Thus, the final answer for the ratio of the discriminants \( D_1 : D_2 \) is: \[ D_1 : D_2 = a^2 : p^2 \]

To solve the problem, we need to find the ratio of the discriminants \( D_1 : D_2 \) for the given quadratic equations. Let's break down the solution step by step. ### Step 1: Identify the roots and their relationships Let \( \alpha \) and \( \beta \) be the roots of the equation \( ax^2 + bx + c = 0 \). According to Vieta's formulas: - The sum of the roots \( \alpha + \beta = -\frac{b}{a} \) - The product of the roots \( \alpha \beta = \frac{c}{a} \) Now, the roots of the second equation \( px^2 + gx + r = 0 \) are \( \alpha + h \) and \( \beta + h \). ...
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