Sa se calculeze: cu logaritmi

[tex] exercitiul \ 1:\\ \\ \log_{49}84-\log_{49}12=\log_{7^2}\frac{84}{12}=-\frac{1}{2}\cdot \log_77=-\frac{1}{2}\\ \\ exercitiul \ 2:\\ \log_2 200 +\log_2 \frac{1}{25}=\log_2 (200\cdot \frac{1}{25})=\log_2 8=\log_2 2^3=3[/tex]