Question

plz help me to solve this
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Answer 1

$\huge{\mathcal{\blue{\underline{Answer}}}}$

Squaring both sides :

$(a + \frac{1}{a} ) {}^{2} = (3) {}^{2} \\ a {}^{2} + \frac{1}{a {}^{2} } + 2( \frac{1}{a} )(a) = 9 \\ a {}^{2} + \frac{1}{a {}^{2} } + 2 = 9 \\ a {}^{2} + \frac{1}{a {}^{2} } = 9 - 2 \\ a {}^{2} + \frac{1}{a {}^{2} } = 7$