Предмет: Алгебра, автор: Zhenehca

Последовательность (Yn)-геометрическая прогрессия.Найдите y8 и y11,если y1=1/81 и q=3

Ответы

Автор ответа: Mgstr2018
0

Используем n-ый член геометрической прогрессии: y_n=y_1q^{n-1}


y_8=y_1q^7=dfrac{1}{81}cdot3^7=27

y_{11}=y_1q^{10}=dfrac{1}{81}cdot3^{10}=729

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