Найдите формулу n-го члена арифметической прогрессии 30; 21; 12; 3; − 6; … . - №31406187

Найдите формулу n-го члена арифметической прогрессии 30; 21; 12; 3; − 6; … .
- Предмет:
  Математика
- Автор:
  cándidaortiz
- 5 лет назад

Ответы 1

Пошаговое объяснение:
a₁ = 30
d = 21 - 30 = -9
aₙ = a₁ + d(n-1) = 30 -9*(n-1) = 39 - 9n
- Автор:
  lorelaifdrf
- 5 лет назад
- 0
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