Предмет: Алгебра, автор: liza8283727

найдите сумму первых трёх членов геометрической прогрессии,если b1=8;q=1/3

Ответы

Автор ответа: KingBrain268

Ответ:

S3 = 11 5/9

Объяснение:

8(1/3^3 - 1) = 8 * (-26/27)

1/3 - 1 = -2/3

(8 * 26 * 3) / (27 * 2) = (8 * 13) / 9 = 104/9 = 11 5/9

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