Question

If x+1/x is 5 then find x2-1/x2

Answer 1

Given:

x + 1/x = 5

To find out:

Find the value of x² + 1/x²

Solution:

x + 1/x = 5

Squaring both sides

( x + 1/x )² = 5²

we know that,

( a + b )² = a² +b² + 2ab

Now,

x² + 1/x² + 2 × x × 1/x = 25

x² + 1/x² + 2 = 25

x² + 1/x² = 23