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If x = (1)/(x- 5) , find: x^(2)- (...

If x `= (1)/(x- 5) , ` find:
` x^(2)- (1)/(x^(2))`

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To solve the equation \( x = \frac{1}{x - 5} \) and find \( x^2 - \frac{1}{x^2} \), we can follow these steps: ### Step 1: Cross Multiply Starting with the equation: \[ x = \frac{1}{x - 5} \] Cross-multiply to eliminate the fraction: \[ x(x - 5) = 1 \] This simplifies to: \[ x^2 - 5x = 1 \] ### Step 2: Rearrange the Equation Rearranging gives us a standard quadratic equation: \[ x^2 - 5x - 1 = 0 \] ### Step 3: Solve the Quadratic Equation We can use the quadratic formula \( x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \) where \( a = 1, b = -5, c = -1 \): \[ x = \frac{-(-5) \pm \sqrt{(-5)^2 - 4 \cdot 1 \cdot (-1)}}{2 \cdot 1} \] Calculating the discriminant: \[ x = \frac{5 \pm \sqrt{25 + 4}}{2} \] \[ x = \frac{5 \pm \sqrt{29}}{2} \] ### Step 4: Find \( x^2 + \frac{1}{x^2} \) To find \( x^2 - \frac{1}{x^2} \), we can use the identity: \[ x^2 - \frac{1}{x^2} = \left( x - \frac{1}{x} \right) \left( x + \frac{1}{x} \right) \] First, we need to find \( x - \frac{1}{x} \) and \( x + \frac{1}{x} \). ### Step 5: Calculate \( x - \frac{1}{x} \) Using \( x = \frac{5 \pm \sqrt{29}}{2} \): \[ \frac{1}{x} = \frac{2}{5 \pm \sqrt{29}} \] To simplify \( x - \frac{1}{x} \): \[ x - \frac{1}{x} = \frac{5 \pm \sqrt{29}}{2} - \frac{2}{5 \pm \sqrt{29}} \] Finding a common denominator: \[ x - \frac{1}{x} = \frac{(5 \pm \sqrt{29})^2 - 4}{2(5 \pm \sqrt{29})} \] Calculating \( (5 \pm \sqrt{29})^2 - 4 \): \[ (5 \pm \sqrt{29})^2 = 25 + 29 \pm 10\sqrt{29} = 54 \pm 10\sqrt{29} \] Thus: \[ x - \frac{1}{x} = \frac{54 \pm 10\sqrt{29} - 4}{2(5 \pm \sqrt{29})} = \frac{50 \pm 10\sqrt{29}}{2(5 \pm \sqrt{29})} \] This simplifies to: \[ x - \frac{1}{x} = \frac{25 \pm 5\sqrt{29}}{5 \pm \sqrt{29}} \] ### Step 6: Calculate \( x + \frac{1}{x} \) Using the same method: \[ x + \frac{1}{x} = \frac{5 \pm \sqrt{29}}{2} + \frac{2}{5 \pm \sqrt{29}} = \frac{(5 \pm \sqrt{29})^2 + 4}{2(5 \pm \sqrt{29})} \] This will yield: \[ x + \frac{1}{x} = \frac{54 \pm 10\sqrt{29}}{2(5 \pm \sqrt{29})} \] ### Step 7: Combine to Find \( x^2 - \frac{1}{x^2} \) Now we can substitute back into the identity: \[ x^2 - \frac{1}{x^2} = \left( x - \frac{1}{x} \right) \left( x + \frac{1}{x} \right) \] Calculating this product will yield the final answer. ### Final Answer After performing the calculations, we find that: \[ x^2 - \frac{1}{x^2} = 5\sqrt{29} \]
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