</font><font face="Arial" color="#000100" size="3">) = rt
</font><font face="Arial" color="#000100" size="2"><sub>i
</sub></font><font face="Arial" color="#000100" size="2"><sup>r - 1
</sup></font><font face="Arial" color="#000100" size="3"><br><br><br>Setting 
</font><font face="Symbol" color="#000100" size="3">m
</font><font face="Arial" color="#000100" size="2"><sub>i
</sub></font><font face="Arial" color="#000100" size="3"> = e
</font><font face="Symbol" color="#000100" size="3"><strong><sup>b
</sup></s