Confirm that f and g are inverses by showing that f(g(x)) = x and g(f(x)) = x.

f of x equals eight divided by x and g of x equals eight divided by x

F(x) = 8/x and g(x) = 8/x

To find f(g(x)), all you do is substitute g(x) into the x value of f(x). 

So f(g(x)) = 8/(8/x) which = x

Similarly g(f(x)) is found by substituting f(x) into the x value of g(x)

g(f(x)) = 8/(8/x) which = x