Question

what can be the value of (y-1/y)² if y²+1/y² = 10​

Answer 1

By using identity : (a - b) Ka whole square.

=y + 1/y -2×y×1/y

=y + 1/y - 2 (Here only 2 remains because both y divides each other and then only 1 remains so 1×2 =2)

=Here the given value of (y rash to power 2) +( 1/y rash to power 2) is 10.

Therefore --- 10-2=8

Therefore our answer is 8.