## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

$\log_b \dfrac{c}{d}$
Using $\log_b x-\log_b y=\log_b \dfrac{x}{y}$ (or the logarithm of a quotient), the given logarithmic equation, $\log_b c-\log_b d ,$ is equivalent to \begin{array}{l}\require{cancel} \log_b \dfrac{c}{d} .\end{array}