If f (x) satisfies f (x) + 2F (1 / x) = 5x + 4 / x, then f (x)=

If f (x) satisfies f (x) + 2F (1 / x) = 5x + 4 / x, then f (x)=

Substituting 1 / x into
f(1/x)+2f(x)=5/x+4x
By subtracting f (1 / x), we get
f(x)=x+2/x