The functions may be approximated as: <br />
  <br />
  



 
  


<br clear="all" /><table border="0" width="100%"><tr><td>
<table align="center"><tr><td nowrap="nowrap" align="center">
 <i>A</i>(<i>x</i>)  <font face="symbol">»</font
> <i>x</i> <font face="symbol">-</font
> </td><td nowrap="nowrap" align="center">
<i>x</i><sup>3</sup><hr noshade="noshade" size="1" />3!<br /></td><td nowrap="nowrap" align="center">
&#x00A0;&#x00A0;&#x00A0; <i>B</i>(<i>x</i>) <font face="symbol">»</font
> </td><td nowrap="nowrap" align="center">
<i>x</i><sup>2</sup><hr noshade="noshade" size="1" />2!<br /></td><td nowrap="nowrap" align="center">
<font face="symbol">-</font
></td><td nowrap="nowrap" align="center">
<i>x</i><sup>4</sup><hr noshade="noshade" size="1" />4!<br /></td><td nowrap="nowrap" align="center">
&#x00A0;&#x00A0;&#x00A0; <i>C</i>(<i>x</i>)  <font face="symbol">»</font
> <i>x</i> <font face="symbol">-</font
> </td><td nowrap="nowrap" align="center">
<i>x</i><sup>2</sup><hr noshade="noshade" size="1" />2<br /></td><td nowrap="nowrap" align="center">
&#x00A0;&#x00A0;&#x00A0; <i>D</i>(<i>x</i>)  <font face="symbol">»</font
> <i>x</i> + <i>x</i><sup>2</sup> </td></tr></table>
</td></tr></table>

 



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