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If x = (1)/(x- 5) , find: x+(1)/(x...

If x `= (1)/(x- 5) , ` find:
` x+(1)/(x)`

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To solve the problem where \( x = \frac{1}{x - 5} \) and we need to find \( x + \frac{1}{x} \), we can follow these steps: ### Step-by-Step Solution: 1. **Start with the given equation**: \[ x = \frac{1}{x - 5} \] 2. **Cross-multiply to eliminate the fraction**: \[ x(x - 5) = 1 \] This simplifies to: \[ x^2 - 5x = 1 \] 3. **Rearrange the equation to form a standard quadratic equation**: \[ x^2 - 5x - 1 = 0 \] 4. **Use the quadratic formula to solve for \( x \)**: The quadratic formula is given by: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] Here, \( a = 1 \), \( b = -5 \), and \( c = -1 \). Plugging in these values: \[ x = \frac{-(-5) \pm \sqrt{(-5)^2 - 4 \cdot 1 \cdot (-1)}}{2 \cdot 1} \] Simplifying this: \[ x = \frac{5 \pm \sqrt{25 + 4}}{2} \] \[ x = \frac{5 \pm \sqrt{29}}{2} \] 5. **Now, calculate \( \frac{1}{x} \)**: Since \( x = \frac{5 \pm \sqrt{29}}{2} \), we find \( \frac{1}{x} \): \[ \frac{1}{x} = \frac{2}{5 \pm \sqrt{29}} \] 6. **Find \( x + \frac{1}{x} \)**: To find \( x + \frac{1}{x} \), we can use the identity: \[ x + \frac{1}{x} = \frac{5 \pm \sqrt{29}}{2} + \frac{2}{5 \pm \sqrt{29}} \] To simplify, we can find a common denominator: \[ x + \frac{1}{x} = \frac{(5 \pm \sqrt{29})^2 + 2}{(5 \pm \sqrt{29})} \] Expanding \( (5 \pm \sqrt{29})^2 \): \[ = 25 + 29 \pm 10\sqrt{29} + 2 = 27 \pm 10\sqrt{29} \] Therefore: \[ x + \frac{1}{x} = \frac{27 \pm 10\sqrt{29}}{(5 \pm \sqrt{29})} \] 7. **Final Result**: We can conclude that: \[ x + \frac{1}{x} = \sqrt{29} \text{ or } -\sqrt{29} \]
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