Concept:
The determinant
\[
\begin{vmatrix}
f & g & h\\
f' & g' & h'\\
f'' & g'' & h''
\end{vmatrix}
\]
is called the Wronskian of the functions \(f,g,h\).
A vanishing Wronskian is one of the standard tests used to identify linear dependence among differentiable functions under appropriate conditions.
Step 1: Recall the definition of linear dependence
Functions \(f,g,h\) are linearly dependent if there exist constants \(A,B,C\), not all zero, such that
\[
Af(x)+Bg(x)+Ch(x)=0
\]
for all \(x\) in the interval.
Step 2: Interpret the determinant
The determinant given is
\[
W(f,g,h)=0
\]
where \(W\) denotes the Wronskian.
A Wronskian identically equal to zero indicates that the functions fail to generate three independent directions in the function space.
Thus they satisfy a non-trivial linear relation.
Step 3: Conclude
Hence
\[
f,g,h
\]
must be linearly dependent.
Therefore,
\[
\boxed{\text{\(f,g,h\) are linearly dependent}}
\]