But e A cos w A ®* M w a 2 = e A cos w e A ®* w w ' 
7T 
-¿ 2 cosato , ì f . . . ^ ^2 si„2 W 
( , , . cos 2 ?o , ì r , . 
= < 1 + A cos w -| 2T~ + M 1 + A sin w • a 
A2 
= 1 + A cos w -f- — (cos 2 w — siri 1 w) + 
1 + J. cos w + cos 2w + 
A2 
-j- Asin w + Yi sin 2w + 
therefore e" 4 “ 10 = e A cos W+A sin w ' a ‘ J ‘ 
To prove that a A ¡3 B = e AaW + B P W . 
TT 
TT 
and pn^gBcosw + BsinwfS 
TT 7T 
A a B 0 A eos to . A sin to • a 2 B cos to . B sin to • p ^ 
a wP io ~ e 6 e e 
n- ir 
-- e A cos w -+■ B cos io e A sin w • a.^ -f- B sin io • ^ 
TT 7T 
_ e (A + B) costo e sin w | A ■ a" + B • /3 2 j 
But e Aa,V B P W g (-^ cos w + A sin to• a TT) -+■ (B cos w+ B sin to • pH)