Question

If X = (3+✓8) , then find the Value of X²+1/X².

Answer 1

Hii friend,

X = (3+✓8)

Therefore,

1/X = 1/(3+✓8) = 1/(3+✓8) × (3-✓8)/(3-✓8) = (3-✓8)/(3)² - (✓8)² = (3-✓8)/(9-8) = 3-✓8/1 = 3-✓8.

1/X = 3-✓8.

Therefore,

=> (X+1/X) = (3+✓8) + (3-✓8) = 3+3 = 6.

=> (X+1/X)² = (6)² = 36

=> (X²+1/X²) +2 × X × 1/X = 36

=> (X²+1/X²) +2 = 36

=> (X²+1/X²) = 36-2

=>(X²+1/X²) = 34..

Hence,

(X²+1/X²) = 34

HOPE IT WILL HELP YOU.... :-)