Question

lf x=(4-√15), find the value of (x+1/x)

Answer 1

нєℓℓσ мαтє!

нєяє ιѕ уσυя ѕσℓυтισи

x = 4 - √15
1/x = 1/ ( 4 - √15 )

On rationalizing we get
1/ ( 4 - √15 ) × ( 4 + √15 )/( 4 + √15 )
( 4 + √15 )/( 16 - 15 ) = 4 + √15

Now, x + 1/x

4 - √15 + 4 + √15 = 8

нσρє ιт нєℓρѕ

Answer 2

1/√x = 1/(4-√15)
rationalize. it
=4+√15/(16-15)
=4+√15
now put it x+1/x
=4-√5+4+√5
=8-√5+√5
=8