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If one root of the quadratic equation 3x...

If one root of the quadratic equation `3x^(2)-10x+k=0` is reciprocal of the other, find the value of k.

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To solve the problem, we need to find the value of \( k \) in the quadratic equation \( 3x^2 - 10x + k = 0 \) given that one root is the reciprocal of the other. ### Step-by-Step Solution: 1. **Let the Roots be Defined**: Let one root be \( r \). Since one root is the reciprocal of the other, the other root will be \( \frac{1}{r} \). 2. **Sum of the Roots**: According to Vieta's formulas, the sum of the roots of the quadratic equation \( ax^2 + bx + c = 0 \) is given by: \[ \text{Sum of roots} = -\frac{b}{a} \] For our equation \( 3x^2 - 10x + k = 0 \), we have \( a = 3 \) and \( b = -10 \). Thus, the sum of the roots is: \[ r + \frac{1}{r} = -\frac{-10}{3} = \frac{10}{3} \] 3. **Product of the Roots**: The product of the roots is given by: \[ \text{Product of roots} = \frac{c}{a} \] In our case, this gives: \[ r \cdot \frac{1}{r} = \frac{k}{3} \] Since \( r \cdot \frac{1}{r} = 1 \), we have: \[ 1 = \frac{k}{3} \] 4. **Solving for \( k \)**: To find \( k \), we multiply both sides of the equation \( 1 = \frac{k}{3} \) by 3: \[ k = 3 \] ### Conclusion: Thus, the value of \( k \) is \( 3 \).
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