sin( &+ Ą = cos(&+ /?} '■
tg[ &+ Ą =
ctg[ a>+ Ą ■■
sin L-ycos^+ cos ^rsin $
= cos i.ycos/?~ sin trsin^
tg a>+ tg/?
1 ~tg ar tg/7
Ctg lT Ctg/?~ 1
ctg &+ ctgfi