Предмет: Алгебра, автор: Afaxriya2001

Помогите с логарифмом.....

Приложения:

Ответы

Автор ответа: artalex74
1
x>0, x≠1
Обе части логарифмируем по основанию 5:
\log_5x^{\log_5x-2}=\log_5125\\ (\log_5x-2)*\log_5x=3\\
log_5x=t\\
(t-2)t=3\\ t^2-2t-3=0\\ t_1=-1,\ t_2=3
Отсюда
1)\ log_5x=-1\ \Rightarrow x= \frac{1}{5}=0,2 \\
2)\ log_5x=3\ \Rightarrow x= 5^3=125 \\
Ответ: 0,2; 125,
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