Question

if
a^2+1/a^2=23
find the value of
(a+1/a)

Answer 1

a² + 1/a² = 23

On adding 2( a × 1/a ) on both sides, we get

a² + 1/a² + 2(a × 1/a ) = 23 + 2(a × 1/a )

( a + 1/a )² = 23 + 2

( a + 1/a )² = 25

( a + 1/a ) = ±√25

( a + 1/a ) = 5 [ taking positive value ]

Answer 2

a^2+1/a^2=(a+1/a)^2-2
23=(a+1/ a)^2-2
(a+1/a)^2=21
a+1/a=under root 21
a+1/a=under root 21