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If alpha and 1/alpha are the zeroes of t...

If `alpha` and `1/alpha` are the zeroes of the quadratic polynomial `2x^2-x+8k`, then k is:

A

4

B

`1/4`

C

`(-1)/4`

D

2

Text Solution

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The correct Answer is:
To solve the problem, we need to find the value of \( k \) given that \( \alpha \) and \( \frac{1}{\alpha} \) are the zeros of the quadratic polynomial \( 2x^2 - x + 8k \). ### Step-by-Step Solution: 1. **Identify the Polynomial and Zeros**: The polynomial is given as: \[ p(x) = 2x^2 - x + 8k \] The zeros of the polynomial are \( \alpha \) and \( \frac{1}{\alpha} \). 2. **Use the Product of Zeros**: The product of the zeros of a quadratic polynomial \( ax^2 + bx + c \) is given by: \[ \text{Product of zeros} = \frac{c}{a} \] Here, \( a = 2 \), \( b = -1 \), and \( c = 8k \). 3. **Calculate the Product of Zeros**: For our polynomial: \[ \alpha \cdot \frac{1}{\alpha} = 1 \] According to the formula: \[ \text{Product of zeros} = \frac{8k}{2} \] Thus, we have: \[ 1 = \frac{8k}{2} \] 4. **Simplify the Equation**: Simplifying the right side: \[ 1 = 4k \] 5. **Solve for \( k \)**: To find \( k \), we rearrange the equation: \[ k = \frac{1}{4} \] ### Conclusion: The value of \( k \) is: \[ \boxed{\frac{1}{4}} \]
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