Ответы на вопрос:
cos2π/5 ·cos2π/3 ·cosπ·cos4π/3·cos5π/3 = = cos72 ·cos(π-π/3) ·(-1)·cos(π+π/3)·cos(2π-π/3)= = - cos72· (-cosπ/3)·(-cosπ/3)·cosπ/3 = -1/8· cos72 = = -1/8 ·[(√5-1)/4] = (1-√5)/32
Популярно: Алгебра
-
ксениякейт14.03.2020 14:56
-
MrKreol06.12.2022 08:42
-
Ученик22160325.02.2021 14:31
-
FaceStoom03.10.2021 08:47
-
natashashvachka07.05.2022 18:37
-
лис888930.01.2021 17:01
-
merey22104.01.2023 10:53
-
рптпfgb15.08.2021 16:39
-
bodik22831.05.2023 05:51
-
мишаиванво06.04.2022 21:18