Siń 390/textdegree cos 420/textd
= ѕin(360/textdegree + 30/textdegre) con(360/textdegree +60/textdegr
=siń 30/texdegree cos 60/ text
Siń 390/textdegree cos 420/textd
= ѕin(360/textdegree + 30/textdegre) con(360/textdegree +60/textdegr
=siń 30/texdegree cos 60/ text