Вычислите:
соs18° cos63°+sin18° sin63° = cos63°соs18°+sin63° sin18° = cos (63°-18°)= cos 45° =√2/2
cos18cos63+sin18sin63=cos(18-63)=cos(-45)=cos(45)=
Вычислите:
соs18° cos63°+sin18° sin63° = cos63°соs18°+sin63° sin18° = cos (63°-18°)= cos 45° =√2/2
cos18cos63+sin18sin63=cos(18-63)=cos(-45)=cos(45)=