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If x=sqrt(2)+1, then find the values of ...

If `x=sqrt(2)+1`, then find the values of the following :
`(i)(1)/(x)" "(ii)x+(1)/(x)" "(iii)x-(1)/(x)" "(iv)x^(2)+(1)/(x^(2))`

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To solve the problem step by step, we will find the values of the expressions given that \( x = \sqrt{2} + 1 \). ### Step 1: Find \( \frac{1}{x} \) Given \( x = \sqrt{2} + 1 \), we can find \( \frac{1}{x} \) by rationalizing the denominator. \[ \frac{1}{x} = \frac{1}{\sqrt{2} + 1} \] To rationalize, multiply the numerator and denominator by \( \sqrt{2} - 1 \): \[ \frac{1}{x} = \frac{\sqrt{2} - 1}{(\sqrt{2} + 1)(\sqrt{2} - 1)} = \frac{\sqrt{2} - 1}{2 - 1} = \sqrt{2} - 1 \] ### Step 2: Find \( x + \frac{1}{x} \) Now, we can find \( x + \frac{1}{x} \): \[ x + \frac{1}{x} = (\sqrt{2} + 1) + (\sqrt{2} - 1) \] Combine like terms: \[ x + \frac{1}{x} = \sqrt{2} + 1 + \sqrt{2} - 1 = 2\sqrt{2} \] ### Step 3: Find \( x - \frac{1}{x} \) Next, we find \( x - \frac{1}{x} \): \[ x - \frac{1}{x} = (\sqrt{2} + 1) - (\sqrt{2} - 1) \] Combine like terms: \[ x - \frac{1}{x} = \sqrt{2} + 1 - \sqrt{2} + 1 = 2 \] ### Step 4: Find \( x^2 + \frac{1}{x^2} \) To find \( x^2 + \frac{1}{x^2} \), we can use the identity: \[ x^2 + \frac{1}{x^2} = \left( x + \frac{1}{x} \right)^2 - 2 \] We already found \( x + \frac{1}{x} = 2\sqrt{2} \). Now square it: \[ \left( x + \frac{1}{x} \right)^2 = (2\sqrt{2})^2 = 8 \] Now, substitute into the identity: \[ x^2 + \frac{1}{x^2} = 8 - 2 = 6 \] ### Summary of Results 1. \( \frac{1}{x} = \sqrt{2} - 1 \) 2. \( x + \frac{1}{x} = 2\sqrt{2} \) 3. \( x - \frac{1}{x} = 2 \) 4. \( x^2 + \frac{1}{x^2} = 6 \)

To solve the problem step by step, we will find the values of the expressions given that \( x = \sqrt{2} + 1 \). ### Step 1: Find \( \frac{1}{x} \) Given \( x = \sqrt{2} + 1 \), we can find \( \frac{1}{x} \) by rationalizing the denominator. \[ \frac{1}{x} = \frac{1}{\sqrt{2} + 1} ...
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