Question

вычислите sin 111°cos21°-sin21°cos111°​

Answer 1

Ответ:

1

Объяснение:

$sin(a-b)=sina*cosb-cosa*sinb$

sin 111°cos21°-sin21°cos111°​=sin 111°cos21°-cos111°​sin21°=sin(111°-21°)=sin90°=1

Answer 2

$\sin111^o\cos21^o-\sin21^o\cos111^o=\sin(111^o-\sin21^o)=\sin90^o=1$