1. The problem is to evaluate the expression $\log_2 7 - \log_{14} 2$.
2. Recall the logarithm subtraction rule: $\log_a b - \log_a c = \log_a \frac{b}{c}$, but here the bases differ, so we need to convert to a common base.
3. Use the change of base formula: $\log_a b = \frac{\log b}{\log a}$ for any positive base (commonly base 10 or $e$).
4. Rewrite each term:
$$\log_2 7 = \frac{\log 7}{\log 2}$$
$$\log_{14} 2 = \frac{\log 2}{\log 14}$$
5. Substitute back:
$$\log_2 7 - \log_{14} 2 = \frac{\log 7}{\log 2} - \frac{\log 2}{\log 14}$$
6. Find a common denominator $\log 2 \cdot \log 14$:
$$= \frac{\log 7 \cdot \log 14}{\log 2 \cdot \log 14} - \frac{\log 2 \cdot \log 2}{\log 14 \cdot \log 2} = \frac{\log 7 \cdot \log 14 - (\log 2)^2}{\log 2 \cdot \log 14}$$
7. Note that $\log 14 = \log (2 \times 7) = \log 2 + \log 7$.
8. Substitute $\log 14$:
$$= \frac{\log 7 (\log 2 + \log 7) - (\log 2)^2}{\log 2 (\log 2 + \log 7)} = \frac{\log 7 \cdot \log 2 + (\log 7)^2 - (\log 2)^2}{\log 2 (\log 2 + \log 7)}$$
9. The numerator is a difference of squares rearranged:
$$= \frac{(\log 7)^2 + \log 7 \cdot \log 2 - (\log 2)^2}{\log 2 (\log 2 + \log 7)}$$
10. This expression is simplified as is; numerical approximation can be done if needed.
Final answer:
$$\log_2 7 - \log_{14} 2 = \frac{(\log 7)^2 + \log 7 \cdot \log 2 - (\log 2)^2}{\log 2 (\log 2 + \log 7)}$$
Logarithm Expression B91612
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