[r]sin α *cos β =[/r]
sin6x+sin(-4x)-sin12x-sin6x=0
-sin4x-sin12x=0
sin4x+sin12x=0
Формула
[r]sin α +sin β =[/r]
2sin8x * cos(-4x)=0
sin8x*cos4x=0
sin8x=0 или cos4x=0
8x=πk, k ∈ [b]Z[/b] или 4x=(π/2)+πn, n ∈ [b]Z[/b]
x=(π/8)k, k ∈ [b]Z[/b] или x=(π/8)+(π/4)*n, n ∈ [b]Z[/b]