Question

if a =5-2√6 then find √a -1/√a

Answer 1

Answer:

x

2

+

x

2

1

=(x−

x

1

)

2

+2

Given, x=5−2

6

.

Then,

x

1

=

5−2

6

1

=

(5−2

6

)(5+2

6

)

5+2

6

=

5

2

−(2

6

)

2

5+2

6

=

25−24

5+2

6

=

1

5+2

6

=5+2

6

.

Then, x

2

+

x

1

=(5−2

6

−(5+2

6

))

2

+2

∴(−4

6

)

2

+2=96+2=98.

Therefore, the required value is 98.