Выполни задание

Запиши в виде произведения:

а) \(\sin80^\degree + \sin40\degree = \) [ ];

б) \(\sin80\degree - \sin40\degree = \) [ ];

в) \(\cos80\degree + \cos80\degree = \) [ ];

г) \(\cos80\degree - \cos40\degree = \) [ ].