116 A NEW METHOD OF DETERMINING 
also 
f = 1+, + periodic terms. 
From these we get 
~— 1p ele w= Fh, 
Hence 
I= — hk, + H, = 3 (hy + ey) + 3 HL; 
or, neglecting the term of the second order, 
K=3(k +e). 
