Предмет: Алгебра, автор: MihailVadimovich2007

параметрами!(8 класс)
При каких значениях параметра «а» произведение корней уравнения x^2+4x-15a^2=0 равно -15?
Готовлюсь к самосте, 1 задачу мне помогли, вторую сам решил, теперь вот с этой проблема. Помогите, пожалуйста!!!

oqilovmehrob: это тоже самая найдеш корней и слогаешь первый и второй корень равно 15

oqilovmehrob: т.е -15

MihailVadimovich2007: Получается так:
Беру дискр.
Дальше ищу x,1 и x,2
И тут мини проблема, в первом икс 5а, а во втором? -8-10а/2 и тогда что далее?

oqilovmehrob: слагаем как 5а+(-8-10а/2)= -15

MihailVadimovich2007: Понял! Спасибо!!!

oqilovmehrob: прости не сумма а произведения

oqilovmehrob: т.е 5а*(-8-10а)= -15

MihailVadimovich2007: Это тонкости, ничего страшного)))

MihailVadimovich2007: В любом случае, спасибо!

Ответы

Автор ответа: olga0olga76

Ответ:

±1

Объяснение:

х²+4х-15а²=0

х1*х2=-15, а—?

Согласно теореме Виета:

х1*х2=-15а²/1

-15=-15а²

а²=-15/(-15)

а²=1

а=±√1

а=±1

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