Question

A^2+1/a^2 = 27, find only a-1/a

Answer 1

Answer:

a-1/a = 5

Step-by-step explanation:

a²+1/a² = 27

(a-1/a)²

= a²+1/a²-2*a*1/a

= a²+1/a²-2

= 27-2

= 25

(a-1/a)² = 25

=> a-1/a = √25

=> a-1/a = 5

Answer 2

$( {a}^{} - \frac{1}{a } {)}^{2} = {a}^{2} + \frac{1}{ {a}^{2} } - 2 \times a \times \frac{1}{a} \\ \\ ( {a - \frac{1}{a}) }^{2} = 27 - 2 \\ \\ (a - \frac{1}{a} {)}^{2} = 25 \\ \\ a - \frac{1}{a} = 5$