Answer
f(28)=3
f(9)=2
f(0)=-1
f(-63)=-4
Work Step by Step
we substitute x for the given value
$f(28)=\sqrt[3] {28-1}=\sqrt[3] {27}=\sqrt[3] {3^3}=3$
$f(9)=\sqrt[3] {9-1}=\sqrt[3] {8}=\sqrt[3] {2^3}=2$
$f(0)=\sqrt[3] {0-1}=\sqrt[3] {-1}=-1$
$f(-63)=\sqrt[3] {-63-1}=\sqrt[3] {-64}=\sqrt[3] {-4^3}=-4$