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If x+ (1)/(x)=1, find x^(12) + (1)/(x...

If `x+ (1)/(x)=1`, find
`x^(12) + (1)/(x^(12))=`

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To solve the equation \( x + \frac{1}{x} = 1 \) and find \( x^{12} + \frac{1}{x^{12}} \), we can follow these steps: ### Step 1: Cube Both Sides We start with the equation: \[ x + \frac{1}{x} = 1 \] Now, we will cube both sides: \[ \left(x + \frac{1}{x}\right)^3 = 1^3 \] This gives us: \[ x^3 + 3x\left(\frac{1}{x}\right)(x + \frac{1}{x}) + \frac{1}{x^3} = 1 \] ### Step 2: Simplify the Expression Using the identity \( a^3 + b^3 + 3ab(a + b) \), we can rewrite the left side: \[ x^3 + \frac{1}{x^3} + 3(x + \frac{1}{x}) = 1 \] Substituting \( x + \frac{1}{x} = 1 \): \[ x^3 + \frac{1}{x^3} + 3(1) = 1 \] This simplifies to: \[ x^3 + \frac{1}{x^3} + 3 = 1 \] ### Step 3: Solve for \( x^3 + \frac{1}{x^3} \) Now, we can isolate \( x^3 + \frac{1}{x^3} \): \[ x^3 + \frac{1}{x^3} = 1 - 3 \] Thus: \[ x^3 + \frac{1}{x^3} = -2 \] ### Step 4: Find \( x^{12} + \frac{1}{x^{12}} \) Next, we need to find \( x^{12} + \frac{1}{x^{12}} \). We can use the identity: \[ x^{n} + \frac{1}{x^{n}} = (x^{k} + \frac{1}{x^{k}})(x^{n-k} + \frac{1}{x^{n-k}}) - (x^{n-k-1} + \frac{1}{x^{n-k-1}}) \] We will calculate \( x^6 + \frac{1}{x^6} \) first. ### Step 5: Calculate \( x^6 + \frac{1}{x^6} \) Using the identity: \[ x^6 + \frac{1}{x^6} = (x^3 + \frac{1}{x^3})^2 - 2 \] Substituting \( x^3 + \frac{1}{x^3} = -2 \): \[ x^6 + \frac{1}{x^6} = (-2)^2 - 2 = 4 - 2 = 2 \] ### Step 6: Calculate \( x^{12} + \frac{1}{x^{12}} \) Now we can find \( x^{12} + \frac{1}{x^{12}} \): \[ x^{12} + \frac{1}{x^{12}} = (x^6 + \frac{1}{x^6})^2 - 2 \] Substituting \( x^6 + \frac{1}{x^6} = 2 \): \[ x^{12} + \frac{1}{x^{12}} = (2)^2 - 2 = 4 - 2 = 2 \] ### Final Answer Thus, the final result is: \[ \boxed{2} \]
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