Question

If x=3/5-√8 find x+1/x

Answer 1

Answer :

1154

Step-by-step explanation:

Given x=3+

8

So

x

1

=

3+

8

1

⋅

3−

8

3−

8

=

9−8

3−

8

=3−

8

Thus x+

x

1

=3+

8

+3−

8

=6

⇒x

2

+

x

2

1

+2⋅x⋅

x

1

=6

2

=36, square both sides

⇒x

2

+

x

2

1

=36−2=34

⇒x

4

+

x

4

1

+2⋅x

2

⋅

x

2

1

=34

2

, square both sides

∴x

4

+

x

4

1

=34

2

−2=1154