To combine \( 4 \log_2 x + 2 \log_2 z \) into a single logarithm, we can use the properties of logarithms.
- Use the power rule: \( a \log_b c = \log_b (c^a) \).
- For \( 4 \log_2 x \), we can write it as \( \log_2 (x^4) \).
- For \( 2 \log_2 z \), we can write it as \( \log_2 (z^2) \).
Now we have: \[ \log_2 (x^4) + \log_2 (z^2) \]
- Use the product rule: \( \log_b a + \log_b c = \log_b (a \cdot c) \).
- Combining the two logarithms gives us: \[ \log_2 (x^4 \cdot z^2) \]
Thus, the expression \( 4 \log_2 x + 2 \log_2 z \) can be expressed as a single logarithm: \[ \log_2 (x^4 z^2) \]
So the final answer is: \[ \log_2 (x^4 z^2) \]