2 sin 68/ cos 34 · cos 124 Подробно, пожалуйста - №29357531

2 sin 68/ cos 34 · cos 124

Подробно, пожалуйста
- Предмет:
  Алгебра
- Автор:
  goonieu7mp
- 6 лет назад

Ответы 1

Учтём, что Cos124 °= Cos(90° + 34°) = -Sin34°
так что наш пример:
- 2Sin68°/Cos34°Sin34° = -4Sin68°/2Cos34°Sin34° = -4Sin68°/Sin68° = -4
- Автор:
  alina94
- 6 лет назад
- 0
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