Respuesta :

[tex]f(x)=\sqrt[]{x}[/tex]

After a translation of 3 units down:

[tex]y=\sqrt[]{x}-3[/tex]

After a reflection across the x-axis:

[tex]\begin{gathered} g(x)=-(\sqrt[]{x}-3) \\ \end{gathered}[/tex]

so, the answer is:

[tex]g(x)=-\sqrt[]{x}+3[/tex]