Respuesta :

Answer:

[tex]\displaystyle \log_7\frac{1}{81}\approx -2.2[/tex]

Step-by-step explanation:

We want to find:

[tex]\displaystyle \log_7{\frac{1}{81}}[/tex]

First, using the quotient rule:

[tex]\displaystyle \log_b\frac{a}{c}=\log_b a-\log_b{c}[/tex]

We can rewrite our expression as:

[tex]=\log_7 1-\log_7 81[/tex]

The logarithm of 1 is always 0. Therefore:

[tex]=-\log_781[/tex]

We can rewrite this as:

[tex]=-\log_7 9\cdot 9[/tex]

Using the product rule:

[tex]\log_b ac=\log_ba+\log_bc[/tex]

This is equivalent to:

[tex]=-(\log_79+\log_79)[/tex]

Substitute:

[tex]=-(1.1+1.1)=-2.2[/tex]