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Two students while solving a quadratic equation in x, one copied the constant term incorrectly and got the roots 3 and 2. The other copied the constant term and coefficient of `x^(2)` correctly as -6 and 1 respectively. The correct roots are

A

3,-2

B

`-3,2`

C

`-6,-1`

D

`6,-1`

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To solve the problem, we need to determine the correct roots of the quadratic equation based on the information provided about the two students. ### Step-by-Step Solution: 1. **Understanding the Roots from the First Student:** - The first student obtained the roots 3 and 2. - According to the properties of quadratic equations, the sum of the roots (α + β) is given by: \[ \alpha + \beta = 3 + 2 = 5 \] 2. **Understanding the Roots from the Second Student:** - The second student copied the constant term (c) and the coefficient of \(x^2\) (a) correctly as -6 and 1, respectively. - Therefore, the quadratic equation can be represented as: \[ x^2 + bx - 6 = 0 \] - The product of the roots (α * β) is given by: \[ \alpha \cdot \beta = -6 \] 3. **Setting Up the Equations:** - From the first student's roots, we have: \[ \alpha + \beta = 5 \quad \text{(1)} \] - From the second student's roots, we have: \[ \alpha \cdot \beta = -6 \quad \text{(2)} \] 4. **Using the Sum and Product of Roots:** - We can use the equations (1) and (2) to form a quadratic equation. The general form of a quadratic equation based on sum and product of roots is: \[ x^2 - (\alpha + \beta)x + (\alpha \cdot \beta) = 0 \] - Substituting the values from equations (1) and (2): \[ x^2 - 5x - 6 = 0 \] 5. **Factoring the Quadratic Equation:** - To factor the equation \(x^2 - 5x - 6\), we look for two numbers that multiply to -6 and add to -5. These numbers are -6 and 1. - Thus, we can factor the equation as: \[ (x - 6)(x + 1) = 0 \] 6. **Finding the Roots:** - Setting each factor to zero gives us the roots: \[ x - 6 = 0 \quad \Rightarrow \quad x = 6 \] \[ x + 1 = 0 \quad \Rightarrow \quad x = -1 \] ### Conclusion: The correct roots of the quadratic equation are \(6\) and \(-1\).
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