Question

Знатоки логарифмов!!!$12. frac{1}{ log_{8} 0,75} - frac{1}{ log_{6} 0,75} + log_{ sqrt{2} } 0,5=??? 13. frac{ log_{ sqrt[3]{2} } 28}{ log_{32}2 } - frac{ log_{ sqrt[5]{2} } 7}{ log_{8} 2} =???$

Answer 1

12
1/log(8)0,75=log(0,75)8
1/log(3)0,75=log(0,75)6
log(√2)0,5=-2
log(0,75)8-log(0,75)6-2=log(3/4)4/3 -2=-1-2=-3
13
Перейдем к основанию 2
(log(2)7+2)*log(2)32/log(2)∛2=5(log(2)7+2):1/3=15(log(2)7+2)
log(2)7*log(2)8/log(2)(2^1/5)=3log(2)7:1/5=15log(2)7
15(log(2)7+2)-15log(2)7=15log(2)7+30-15log(2)7=30