Предмет: Алгебра, автор: malllboroxx

В арифметической прогрессии d= -3, а8= 3. Найдите а1.

say654: отметь, пожалуйста, как лучший ответ, если так считаешь

Ответы

Автор ответа: say654
1

a(n) = a1 + d×(n-1)

а8 = a1 + 7d

a1 + 7×(-3) = 3

a1 - 21 = 3

a1 = 21 + 3 = 24

say654: отметь как лучший, пожалуйста, если так считаешь
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