Question

20. If x+1/x=8, find the value of x²+1/x?.​

Answer 1

Answer:

62     or  8

Step-by-step explanation:

Given, x + 1/x = 8

             Square on both sides:

⇒ (x + 1/x)² = 8²

⇒ x² + (1/x)² + 2(x * 1/x) = 64

⇒ x² + 1/x² + 2(1) = 64

⇒ x² + 1/x² = 64 - 2

⇒ x² + 1/x² = 62

     ∴ The required value of x² + 1/x² is 62.

If your question is:  (x² + 1)/x

⇒  (x² + 1)/x

⇒ (x²/x) + (1/x)      [reverse step of taking LCM]

⇒ x + 1/x

⇒ 8                   [given in question]