To express each vector as a linear combination of the vectors in set \( S = \{(1,2,-2),(2,-1,1)\} \), we need to find scalars \( a \) and \( b \) such that for a given vector \( v \), \( v = a \cdot (1,2,-2) + b \cdot (2,-1,1) \). This involves solving a system of linear equations for each vector.
We need to express each given vector as a linear combination of the vectors in the set \( S = \{(1, 2, -2), (2, -1, 1)\} \). This means finding scalars \( a \) and \( b \) such that for a given vector \( v \), \( v = a \cdot (1, 2, -2) + b \cdot (2, -1, 1) \).
For each vector, we set up a system of linear equations based on the components of the vectors:
For vector \( z = (-5, -5, 5) \):
\[
\begin{align_}
a + 2b &= -5 \\
2a - b &= -5 \\
-2a + b &= 5
\end{align_}
\]
For vector \( v = (-2, -5, 5) \):
\[
\begin{align_}
a + 2b &= -2 \\
2a - b &= -5 \\
-2a + b &= 5
\end{align_}
\]
For vector \( w = (2, -16, 16) \):
\[
\begin{align_}
a + 2b &= 2 \\
2a - b &= -16 \\
-2a + b &= 16
\end{align_}
\]
We attempt to solve each system of equations to find the values of \( a \) and \( b \). If the system has no solution, it means the vector cannot be expressed as a linear combination of the vectors in \( S \).
For each vector, the system of equations was found to be inconsistent, meaning there is no solution for \( a \) and \( b \). Therefore, each vector cannot be expressed as a linear combination of the vectors in \( S \).
- For vector \( z = (-5, -5, 5) \): \(\boxed{\text{IMPOSSIBLE}}\)
- For vector \( v = (-2, -5, 5) \): \(\boxed{\text{IMPOSSIBLE}}\)
- For vector \( w = (2, -16, 16) \): \(\boxed{\text{IMPOSSIBLE}}\)