Question

a+1/a=9 find the value of a2+1/a2​

Answer 1

Answer

Sure!

a+1/a=9

Squaring both sides we get

$(a+1/a)^{2}$= 9*9

$(a+1/a)^{2}$= 81

Now according to formula of expansion

$(a+1/a)^{2}$= $a^{2}$+1/$a^{2}$+2

So,

$a^{2}$+ 1/$a^{2}$ +2= 81

$a^{2} +\frac{1}{a^{2} }$ = 81-2

79

Hope this helps u :)

Answer 2

EXPLANATION.

⇒ (a + 1/a) = 9.

As we know that,

Squaring on both sides of the equation, we get.

⇒ (a + 1/a)² = (9)².

⇒ (a)² + (1/a)² + 2(a)(1/a) = 81.

⇒ a² + 1/a² + 2 = 81..

⇒ a² + 1/a² = 81 - 2.

⇒ a² + 1/a² = 79.