We need to find two functions f(x) and g(x) such that f(g(x)) = h(x)
[tex]h(x)=\frac{4}{(5x+2)^2}[/tex]f(g(x)) means the value of f(x) will be evaluated at g(x)
Using trial and error :
Let say :
[tex]f(x)=\frac{4}{x^2}[/tex]Replacing x as g(x)
[tex]f(g(x))=\frac{4}{(g(x))^2}[/tex]From here, we can say that g(x) = 5x + 2
So we have :
[tex]\begin{gathered} f(x)=\frac{4}{x^2} \\ g(x)=5x+2 \end{gathered}[/tex]