Lovene for Lysets Forplantelse. 237 



b.cos(jA— x;= — „2 



c.cos(v— x)= 



(428) 



— p?nu(1— tji) 



c'sîn(V— xO=-T-^==* 



Subslitiieres disse Værdier i Lîgningerne (419)5 saa 

 erholdes: 



PM1)(1— y.) . , s 



- 7 p:^^ cos (fct — «I + x) ; 



; =— =3L= sin (kï — st 4- x) — 



'' „a x cos (lit — st + X) ; 



(129) 



£'=P-3^^!±Ücos(fer-st + X') 

 k 



q'w 



