{x - (1/x)} = 4 হলে, {x2 + (1/x2)} কত ?

{x - (1/x)} = 4 হলে, {x² + (1/x²)} কত ?

A 18

B 16

C 14

D 22

Solution

Correct Answer: Option A

প্রদত্তরাশি, {x²+(1/x²) }
= {x-(1/x)}² + 2.x.(1/x)

= 4² + 2

= 16 + 2 = 18