496 BARON VON WREDE ON THE ABSORPTION OF LIGHT 
+ (m—2) (1 — ryt sing 22! 
+..(m—n) (1 air ei dale sinn.2n="] 
If we now put the coefficients of sin 2 (: _ x) equal to A’ cos z, 
and the coefficients of cos 2 7 (¢ — x) equal to A! sinz, we obtain 
U! =A! [ sin an(¢— a) cos z — cos an(¢— 9) sini | 
A a 
= A! sin EGare -i]. 
Whence it follows that A’ becomes the intensity of the resulting system 
of waves of light. 
If we multiply A! sin ¢ with ./—1, and add it to A! cos2, and put 
for shortness 
(i —r) (cosaw 22 4 v/—1. sin 27 2°) 
A A 
equal to p, remembering that 
cosmz + V—1 . Sinmz = (cosz + Pl. sin z)”, 
we obtain 
A! (cosi + “—1 . sin?) 
=a.(1—r)" 78 (cos 29 2° + afi sin ©) 
—l 
x(@—=1) + (m—2)p+ (m — 3) p®? +....(m—n) p- ).-9) 
If we call ((m—1) +(m— 2) p + (m—8)p* +...) 
for the sake of shortness S, we have 
S=(m-l) At+pt+p +P tpt . ae 
“APP tet pte) 
— (+p? +p + Cte te +p") 
Sass atiaht AY Fi nignseatelins + yay) 
n—1 
