Answer :

To solve the expression [tex]\(\log_6\left(\frac{1}{216}\right)\)[/tex], let's break it down step by step:

1. Understand the expression: We are given [tex]\(\log_6\left(\frac{1}{216}\right)\)[/tex], which asks for the exponent to which we must raise the base 6 to obtain [tex]\(\frac{1}{216}\)[/tex].

2. Rewrite the logarithm using properties of exponents:
[tex]\[ \log_6\left(\frac{1}{216}\right) = \log_6 \left(216^{-1}\right) \][/tex]
This uses the property [tex]\( \frac{1}{a} = a^{-1} \)[/tex].

3. Apply the logarithm power rule: The power rule for logarithms states [tex]\(\log_b(a^c) = c \cdot \log_b(a)\)[/tex].
[tex]\[ \log_6 \left(216^{-1}\right) = -1 \cdot \log_6(216) \][/tex]
So, the expression simplifies to:
[tex]\[ \log_6 \left(\frac{1}{216}\right) = -\log_6(216) \][/tex]

4. Evaluate [tex]\(\log_6(216)\)[/tex]:

We need to think about what power 6 must be raised to in order to equal 216. We check:
[tex]\[ 6^1 = 6 \][/tex]
[tex]\[ 6^2 = 36 \][/tex]
[tex]\[ 6^3 = 216 \][/tex]
Since [tex]\(6^3 = 216\)[/tex], we can write:
[tex]\[ \log_6(216) = 3 \][/tex]

5. Combine the results:
[tex]\[ \log_6 \left(\frac{1}{216}\right) = -\log_6(216) = -3 \][/tex]

So, the answer is:
[tex]\[ \boxed{-3} \][/tex]