Option B is correct. The required composite function where f(g(x)) is x is f (x) = StartFraction 2 Over x EndFraction and g (x) = StartFraction 2 Over x EndFraction
Composite functions are functions written inside another function e.g f(g(x))
Given the expressions
f(x) = 2/x
g(x) = 2/x
We are to find the composite function f(g(x))
f(g(x)) = f(2/x)
f(2/x) = (2/(2/x))
f(2/x) = 2 * x/2
f(2/x) = x
Hence the required composite function where f(g(x)) is x is f (x) = StartFraction 2 Over x EndFraction and g (x) = StartFraction 2 Over x EndFraction