If y=f(x)satisfy the conditionfx+1x=x2+1x2   (x≠0)then f(x)is

Given,fx+1x=x2+1x2x≠0⇒fx+1x=x+1x2-2put  x+1x=t⇒f(t)=t2-2 ⇒f(x)=x2-2 ∴x∈[2,∞)