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If alpha, beta be the roots of ax^(2)+2b...

If `alpha, beta` be the roots of `ax^(2)+2bx+c=0 and alpha + delta, beta + delta` be those of `Ax^(2)+2Bx+C=0`, then the value of `(b^(2)-ac)//(B^(2)-AC)` is

A

`((a)/(A))^(2)`

B

`((A)/(a))^(2)`

C

0

D

1

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The correct Answer is:
To solve the problem, we need to find the value of \(\frac{b^2 - ac}{B^2 - AC}\) given that \(\alpha, \beta\) are the roots of the quadratic equation \(ax^2 + 2bx + c = 0\) and \(\alpha + \delta, \beta + \delta\) are the roots of the quadratic equation \(Ax^2 + 2Bx + C = 0\). ### Step-by-Step Solution: 1. **Identify the Roots of the First Equation:** The roots of the first equation \(ax^2 + 2bx + c = 0\) are \(\alpha\) and \(\beta\). By Vieta's formulas: - Sum of roots: \(\alpha + \beta = -\frac{2b}{a}\) - Product of roots: \(\alpha \beta = \frac{c}{a}\) **Hint:** Use Vieta's formulas to relate the coefficients of the polynomial to the roots. 2. **Identify the Roots of the Second Equation:** The roots of the second equation \(Ax^2 + 2Bx + C = 0\) are \(\alpha + \delta\) and \(\beta + \delta\). Again using Vieta's formulas: - Sum of roots: \((\alpha + \delta) + (\beta + \delta) = -\frac{2B}{A}\) - Product of roots: \((\alpha + \delta)(\beta + \delta) = \frac{C}{A}\) **Hint:** Remember that the sum of the roots changes with the addition of \(\delta\). 3. **Express the Sum of Roots for the Second Equation:** The sum of the roots can be expressed as: \[ \alpha + \beta + 2\delta = -\frac{2B}{A} \] Substituting \(\alpha + \beta = -\frac{2b}{a}\): \[ -\frac{2b}{a} + 2\delta = -\frac{2B}{A} \] Rearranging gives: \[ 2\delta = -\frac{2B}{A} + \frac{2b}{a} \] Simplifying, we find: \[ \delta = -\frac{B}{A} + \frac{b}{a} \] **Hint:** Isolate \(\delta\) to find its value in terms of \(b, B, a, A\). 4. **Express the Product of Roots for the Second Equation:** The product of the roots can be expressed as: \[ (\alpha + \delta)(\beta + \delta) = \alpha\beta + \delta(\alpha + \beta) + \delta^2 \] Substituting the known values: \[ \frac{c}{a} + \delta\left(-\frac{2b}{a}\right) + \delta^2 = \frac{C}{A} \] Rearranging gives: \[ \frac{c}{a} + \delta\left(-\frac{2b}{a}\right) + \delta^2 = \frac{C}{A} \] **Hint:** Use the expressions for \(\alpha\) and \(\beta\) to relate the product of roots. 5. **Equate the Two Expressions:** From the two equations derived from the roots, we can set up a ratio: \[ \frac{b^2 - ac}{B^2 - AC} = \frac{a^2}{A^2} \] **Hint:** Recognize that both expressions for the roots lead to a common form that can be simplified. 6. **Final Result:** Thus, the value of \(\frac{b^2 - ac}{B^2 - AC}\) simplifies to: \[ \frac{b^2 - ac}{B^2 - AC} = \frac{a^2}{A^2} \] **Conclusion:** The final answer is \(\frac{a^2}{A^2}\).
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