Answer
$f(7)=2
,\\\\
f(26)=3
,\\\\
f(-9)=-2
,\\\\
f(-65)=-4$
Work Step by Step
$\bf{\text{Solution Outline:}}$
Substitute the given function value in $
f(x)=\sqrt[3]{x+1}
.$
$\bf{\text{Solution Details:}}$
If $
x=7
,$ then
\begin{array}{l}\require{cancel}
f(x)=\sqrt[3]{x+1}
\\\\
f(7)=\sqrt[3]{7+1}
\\\\
f(7)=\sqrt[3]{8}
\\\\
f(7)=2
.\end{array}
If $
x=26
,$ then
\begin{array}{l}\require{cancel}
f(x)=\sqrt[3]{x+1}
\\\\
f(26)=\sqrt[3]{26+1}
\\\\
f(26)=\sqrt[3]{27}
\\\\
f(26)=3
.\end{array}
If $
x=-9
,$ then
\begin{array}{l}\require{cancel}
f(x)=\sqrt[3]{x+1}
\\\\
f(-9)=\sqrt[3]{-9+1}
\\\\
f(-9)=\sqrt[3]{-8}
\\\\
f(-9)=-2
.\end{array}
If $
x=-65
,$ then
\begin{array}{l}\require{cancel}
f(x)=\sqrt[3]{x+1}
\\\\
f(-65)=\sqrt[3]{-65+1}
\\\\
f(-65)=\sqrt[3]{-64}
\\\\
f(-65)=-4
.\end{array}
Hence,
\begin{array}{l}\require{cancel}
f(7)=2
,\\\\
f(26)=3
,\\\\
f(-9)=-2
,\\\\
f(-65)=-4
.\end{array}
