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If a^2 + (1)/( a^2 ) = 2, find : (i) a+ ...

If `a^2 + (1)/( a^2 ) = 2`, find : (i) `a+ (1)/( a)`

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To solve the problem, we start with the given equation: **Given:** \[ a^2 + \frac{1}{a^2} = 2 \] We need to find the value of \( a + \frac{1}{a} \). ### Step 1: Use the identity We know the identity: \[ (a + b)^2 = a^2 + b^2 + 2ab \] In our case, let: - \( a = a \) - \( b = \frac{1}{a} \) Then: \[ (a + \frac{1}{a})^2 = a^2 + \frac{1}{a^2} + 2 \cdot a \cdot \frac{1}{a} \] ### Step 2: Simplify the expression The expression simplifies to: \[ (a + \frac{1}{a})^2 = a^2 + \frac{1}{a^2} + 2 \] ### Step 3: Substitute the known value We know from the problem statement that: \[ a^2 + \frac{1}{a^2} = 2 \] Substituting this into our equation gives: \[ (a + \frac{1}{a})^2 = 2 + 2 \] ### Step 4: Calculate the right side Now, calculate the right side: \[ (a + \frac{1}{a})^2 = 4 \] ### Step 5: Take the square root To find \( a + \frac{1}{a} \), we take the square root of both sides: \[ a + \frac{1}{a} = \sqrt{4} \] ### Step 6: Final answer Thus: \[ a + \frac{1}{a} = 2 \] ### Summary of the solution: The value of \( a + \frac{1}{a} \) is 2. ---
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