Предмет: Математика, автор: muhchun

Арифметическая прогрессия содержит 20 членов. Сумма членов с четными номерами на 80 больше суммы членов с нечетными номерами. Найдите разность прогрессии

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Автор ответа: topkuznetsky17

0

Cумма членов арифметической прогрессмм равна произведению суммы крайних членов на число пар ( 2а + 20 d )5 - (2a + 18d )5 = 80 d = 8

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