SSC CGL 2023 PYQ — Question 65

The correct answer is option 4 i.e. 5778.

Given, y - 1/y = 4

Squarying both sides,

⇒ $y^2 + {1 \over y^2} -2 = 16$

⇒ $y^2 + {1 \over y^2} = 18$  

Cubing both sides of the above equation,

⇒ $(y^2 + {1 \over y^2})^3 = 18^3$

⇒ $y^6 + {1\over y^6} +3(y^2 + {1 \over y^2}) = 5832$

⇒ $y^6 + {1\over y^6} = 5832 - 3(18)$

⇒ $y^6 + {1\over y^6} = 5778$