Question

cos(п/6+B)-cos (п/6-B) (срочно помогите)​

Answer 1

Объяснение:

$cos(\frac{\pi }{6}+\beta )-cos(\frac{\pi }{6} -\beta )=-2*sin{\frac{\frac{\pi }{6}+\beta-\frac{\pi }{6}+\beta }{2} }*sin\frac{\frac{\pi }{6}+\beta +\frac{\pi }{6} -\beta }{2} } =\\ =-2*sin(\beta )*sin\frac{\pi }{6}=-2*sin(\beta )*\frac{1 }{2} =-sin(\beta ).$