[ 36 ] 



G= + 2 



u — I 



G + H = +2 X ''' 



n—u -1^2 « — u — I. « — «/ + I - to terms 



I. 2. 3 - - 2 



« — I 



terms 



K — I 

 to terms 



« — I 

 I. 2. 3 - - to — — terms. 



Hence it appears that if the general terms are rightly exprefled 

 for the fine and cofine of /; — i a, they are alfo rightly exprefled for 

 the fine and cofine of n^, confequently if they are true in the inferior 

 values of n they are true in the fuperior, but they are true in tlic 

 inferior •.• &c. &c. 



III. Cor. If the feries be arranged in a contrary order : 



I. When 



