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If a^(2)+1/(a^(2))=7, find the value of ...

If `a^(2)+1/(a^(2))=7`, find the value of
`(a+1/(a))`

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The correct Answer is:
To solve the problem, we need to find the value of \( a + \frac{1}{a} \) given that \( a^2 + \frac{1}{a^2} = 7 \). ### Step-by-Step Solution: 1. **Recall the Algebraic Identity**: We know that: \[ \left(a + \frac{1}{a}\right)^2 = a^2 + 2 + \frac{1}{a^2} \] This can be rearranged to express \( a^2 + \frac{1}{a^2} \): \[ a^2 + \frac{1}{a^2} = \left(a + \frac{1}{a}\right)^2 - 2 \] 2. **Substitute the Given Value**: We are given that: \[ a^2 + \frac{1}{a^2} = 7 \] Substitute this into the rearranged identity: \[ 7 = \left(a + \frac{1}{a}\right)^2 - 2 \] 3. **Solve for \( \left(a + \frac{1}{a}\right)^2 \)**: Add 2 to both sides: \[ 7 + 2 = \left(a + \frac{1}{a}\right)^2 \] \[ 9 = \left(a + \frac{1}{a}\right)^2 \] 4. **Take the Square Root**: Now, take the square root of both sides: \[ a + \frac{1}{a} = \sqrt{9} \] \[ a + \frac{1}{a} = 3 \quad \text{(since we consider only the positive root)} \] 5. **Final Answer**: Thus, the value of \( a + \frac{1}{a} \) is: \[ \boxed{3} \]
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