Фотий
6 год назад
Cos3xcosx-sin3xsinx =
ОТВЕТЫ
Sysoevich
Jul 7, 2019
Cos3x*cosx -sin3x*sinx = -1/2 ;
cos(3x+x) = -1/2 ;
cos4x = -1/2 ;
4x = +,- 2π/3 +2πn ,n∈Z.
x = +,- π/6 +(π/2)*n ,n∈Z.
cos(3x+x) = -1/2 ;
cos4x = -1/2 ;
4x = +,- 2π/3 +2πn ,n∈Z.
x = +,- π/6 +(π/2)*n ,n∈Z.
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