It seems like you're dealing with an expression involving logarithms:

$\log a - z \log b$

If you would like me to solve or simplify this, I can provide a few steps depending on the context. For example, it can be rewritten using properties of logarithms, such as:

$\log a - z \log b = \log \left( a \right) - \log \left( b^z \right)$

Which can then be simplified as:

$\log \left( \frac{a}{b^z} \right)$

Would you like to explore more steps or clarify the context of this expression (e.g., solving for a variable, evaluating with specific values, etc.)?

---

Related questions:

1. How can logarithms with different bases be converted into a common base?
2. What is the change of base formula for logarithms?
3. How do you solve equations involving logarithms?
4. What does the logarithmic rule for powers (i.e., $\log b^z = z \log b$) mean?
5. How can logarithms help in solving exponential equations?

Tip: Always remember that logarithms are the inverse of exponentiation. They are useful in simplifying expressions where the variable is in an exponent.