Question

Помогите решить 8-10 задание

Answer 1

================== 8 ==================

$lg 8 + lg 5 + lg 2.5 = lg (8 cdot 5 cdot 2.5) = lg 100 = lg 10^2 = 2$

================== 9 ==================

$log_29 - log_25 + log_{0.5} 1.8=log_2 frac{9}{5} + log_{frac{1}{2} } 1 frac{8}{10} =\ =log_2 frac{9}{5} - log_2 frac{9}{5} =log_2 (frac{9}{5}:frac{9}{5}) =\ =log_2 1 = 0$

================== 10 ==================
$frac{log_2 125}{log_20.2}=log_{0.2}125 = -log_55^3=-3$