SSC CHSL 2021 PYQ — Question 70

The correct answer is Option 1 i.e.$99{{1} \over 2}$

Given:

$x-3={{1} \over 2x}$ ⇒ $x-{{1} \over 2x} = 3$

Explanation:

According to the given question,

$x-{{1} \over 2x} = 3$

Squarying both sides, we get

$x^2 +{1 \over 4x^2} - 1 = 9$

$x^2 +{1 \over 4x^2} = 10$

Now, again squarying both sides, we get

$x^4 +{1 \over 16x^4} + {1 \over 2} = 100$

$x^4 +{1 \over 16x^4} = 100 - {1 \over 2}$ = $99{{1} \over 2}$

Hence the required answer is $99{{1} \over 2}$ .