A><IMG
 WIDTH="199" HEIGHT="39" BORDER="0"
 SRC="img66.png"
 ALT="\begin{displaymath}
\left( \begin{array}{c}
u_1 \\ u_2
\end{array} \right) =
...
...ight)
\left( \begin{array}{c} v_1 \\ v_2
\end{array} \right)
\end{displaymath}"></TD>
<TD WIDTH=10 ALIGN="RIGHT">
(2.10)</TD></TR>
</TABLE>
<BR CLEAR="ALL"></DIV><P></P>
In general the transformation will be of the form
<BR>
<DIV ALIGN="RIGHT">

<!-- MATH
 \begin{equation}
u = Wv
\end{equation}
 -->
<TABLE WIDTH="100%" ALIGN="CENTER">
<TR VALIGN="MIDDLE"><TD A