Question

If x - 1/x = 4, then find the value of x + 1/x​

Answer 1

Step-by-step explanation:

x - 1/x = 4

Squaring,

x² + 1/x² - 2× x×1/x = 4²

=> x² + 1/x² = 16+2 = 18

=> x² + 1/x² + 2 = 20

=> (x+1/x)² = 20

=> (x+1/x) = √20