Предмет: Алгебра, автор: Аноним

Найдите S7 геометрической прогрессии (bn), если b1=-32; q=1/2.

Ответы

Автор ответа: Evgenia4836

Ответ:

Объяснение:

S7= -32*(1/128 -1)/(1/2-1)= -63,5

Evgenia4836: формула n*(2a1+d(n-1))/2

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