Question

Use the change of base formula to evaluate the expression.log subscript 13 21=

Answer 1

Answer:
`\log _(13)21=1.187`Step-by-step explanation:

Note the change of base rule below

`\log _ab=(\log _cb)/(\log _ca)`

The given logarithmic expression is:

`\log _(13)21`

Applying the change of base rule

`\log _(13)21=(\log _(10)21)/(\log _(10)13)`

Note that:

`\begin{gathered} \log _(10)21=1.3222 \\ \log _(10)13=1.1139 \end{gathered}`

The evaluation therefore becomes:

`\begin{gathered} \log _(13)21=(1.3222)/(1.1139) \\ \log _(13)21=1.187 \end{gathered}`