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If`alpha and beta` are the roots of the equation `ax^(2)+bx+c=0,` then what are the roots of the equation `cx^(2) + bx + a = 0 ` ?

A

` beta , 1/alpha`

B

` alpha, 1/beta`

C

` -alpha, - beta`

D

` 1/alpha, 1/beta`

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The correct Answer is:
To find the roots of the equation \( cx^2 + bx + a = 0 \) given that \( \alpha \) and \( \beta \) are the roots of the equation \( ax^2 + bx + c = 0 \), we can follow these steps: ### Step 1: Understand the given information We know that \( \alpha \) and \( \beta \) are the roots of the equation \( ax^2 + bx + c = 0 \). From Vieta's formulas, we can derive the following: - Sum of the roots: \[ \alpha + \beta = -\frac{b}{a} \] - Product of the roots: \[ \alpha \beta = \frac{c}{a} \] ### Step 2: Analyze the new equation Now, we need to analyze the equation \( cx^2 + bx + a = 0 \). Again, using Vieta's formulas, we can find the sum and product of the roots of this equation: - Sum of the roots (let's call them \( p \) and \( q \)): \[ p + q = -\frac{b}{c} \] - Product of the roots: \[ pq = \frac{a}{c} \] ### Step 3: Relate the roots of the new equation to the original roots We will express the sum and product of the roots \( p \) and \( q \) in terms of \( \alpha \) and \( \beta \). 1. **Sum of the roots**: We have: \[ p + q = -\frac{b}{c} \] From the first equation, we know that: \[ \alpha + \beta = -\frac{b}{a} \] To relate these, we can multiply \( \alpha + \beta \) by \( \frac{a}{c} \): \[ \frac{a}{c}(\alpha + \beta) = -\frac{b}{c} \] Thus, we can conclude: \[ p + q = \frac{a}{c}(\alpha + \beta) \] 2. **Product of the roots**: We have: \[ pq = \frac{a}{c} \] From the product of the original roots, we know: \[ \alpha \beta = \frac{c}{a} \] To relate these, we can multiply \( \alpha \beta \) by \( \frac{c}{a} \): \[ \frac{c}{a}(\alpha \beta) = \frac{a}{c} \] ### Step 4: Conclusion From the relationships we derived, we can conclude that the roots \( p \) and \( q \) of the equation \( cx^2 + bx + a = 0 \) are related to the roots \( \alpha \) and \( \beta \) of the original equation \( ax^2 + bx + c = 0 \) as follows: If \( \alpha \) and \( \beta \) are the roots of the first equation, then the roots of the second equation \( cx^2 + bx + a = 0 \) are \( \frac{c}{\alpha} \) and \( \frac{c}{\beta} \).

To find the roots of the equation \( cx^2 + bx + a = 0 \) given that \( \alpha \) and \( \beta \) are the roots of the equation \( ax^2 + bx + c = 0 \), we can follow these steps: ### Step 1: Understand the given information We know that \( \alpha \) and \( \beta \) are the roots of the equation \( ax^2 + bx + c = 0 \). From Vieta's formulas, we can derive the following: - Sum of the roots: \[ \alpha + \beta = -\frac{b}{a} ...
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