74 
ME. W. H. L. EUSSELL ON THE CALCHLHS OF SYMBOLS. 
easily see that 
’rV(f)=<?(fK+2^ ^ (p(g)‘!r+ <p(§). 
Hence we shall have 
+?.(?)(?!) 
• ■ • <P3(?) • ’r® + ^2(?K+ “PlC?) • <Po(f ) 
+ {?.(f)+2fc(f) (f 4) 
where we may put 
^§) = ^2{§) + 2^3(^) ;j;^ ) 
^ 0 ? 
''4'iis)— 
2 
_i 
'i'i(g) 'Pi(?) 
+U§)- 
