Question

Вычислить Log c (c/9), если Log c 3 = 5

Answer 1

Ответ:

$log_{c}(3) = 5$

$log_{c}( \frac{c}{9} ) = log_{c}(c) - log_{c}(9) = \\ = 1 - log_{c}( {3}^{2} ) = 1 - 2log_{c}(3) = \\ = 1 - 2 \times 5 = 1 - 10 = - 9$