Answer:
[tex]f(x) = \sqrt[4]{x+6}[/tex]
Step-by-step explanation:
Let [tex]h(x) = \sqrt[4]{x+7}[/tex] and [tex]g(x) = \sqrt[4]{x+1}[/tex]. By some algebraic handling:
[tex]h(x) = \sqrt[4]{(x+1)+6}[/tex]
[tex]h(x) = \sqrt[4]{(\sqrt[4]{x+1} )^{4}+6}[/tex]
But [tex]g(x) = \sqrt[4]{x+1}[/tex]. Therefore:
[tex]f(x) = \sqrt[4]{x+6}[/tex]