Предмет: Математика, автор: mtcbim

арифметическая прогрессия задана формулой an=4-3n
найти сумму a1+a4 решите подробно пожалуйста

Ответы

Автор ответа: MrLyanda

2

при n=1 a1=4-3=1
при n=4 a4=4-12=-8
1-8=-7

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