Предмет: Алгебра, автор: pernik20121

Знайдіть сьомий член арифметичной прогресії,якщо а6++а8=20.
А)5; Б)20; В)10; Г)15.

Ответы

Автор ответа: 904086
27
a6+a8=20
a7=(a6+a8)/2 (по характеристическому свойству арифметич. прогрессии)
a7=20/2=10 (В)
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Раскройте скобки и напишите перевод каждого предложения
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