Question

a2+1/a2=5 ,find the value of a+1/a

Answer 1

Hey

${a}^{2} + \frac{1}{ {a}^{2} } + 2 =7$

$(a + \frac{1}{a} ) = + \sqrt{7} \: or \: - \sqrt{7}$

Answer 2

${a}^{2} + \frac{1}{ {a}^{2} } = 5$
$= > (a + \frac{1}{a} ) ^{2} - 2 \times a \times \frac{1}{a} = 5$
$= > {(a + \frac{1}{a} )}^{2} = 7$
$so... \\ a + \frac{1}{a} = + - \sqrt{7}$