Question

Простейшие логорифмы. Срочно.

Answer 1

9) 0.5
10) $3^{-2log_{3}5}+log_{3}1= 3^{log_{3}5^{-2}}+0=5^{-2}= \frac{1}{5^2} = \frac{1}{25}=0,04;$
11) $3^{1-log_{2}7} = 0,137301;$
12)$25^{log_{5} 2}*2^{log_{2}10}=(5^2)^{log_{5}2}*10=5^{2log_{5}2}*10=5^{log_{5}2^2}*10=2^2*10= \\=4*10=40; \\-$
$13)$ $(log_{3}2+3log_{3}0,25)/(log_{3}28-log_{3}7)= \\=(log_{3}2+log_{3}2^{-2})/(log_{3}28-log_{3}7)= \\=(log_{3}2+3*(-2log_{3}2))/(log_{3}28-log_{3}7)= \\=(log_{3}2-6log_{3}2)/(log_{3}28-log_{3}7)= \\=(-5log_{3}2)/(log_{3}28-log_{3}7)= \\=- \frac{5log_{3}2}{log_{3}28-log_{3}7}= \\=- \frac{5log_{3}2}{log_{3}2^2}= \\=- \frac{5log_{3}2}{2log_{3}2}= \\=- \frac{5}{2} =-2,5;$