Chapter 7 Exponential and Logarithmic Functions - Mixed Review of Problem Solving - Lessons 7.5-7.7 - Page 537: 2a

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By applying the log rules: $1200\log_2\frac{E_4}{C_4}-1200\log_2\frac{G_4}{E_4}\\=log_2(\frac{E_4}{C_4})^{1200}-\log_2(\frac{G_4}{E_4})^{1200}\\=log_2\frac{(E_4/C_2)^{1200}}{(G_4/E_4)^{1200}}\\=\log_2(\frac{E_4}{C_4}.\frac{E_4}{G_4})^{1200}\\=\log_2(\frac{(E_4)^2}{C_4.G_4})^{1200}$