1. The problem is to find the value of $x$ that satisfies the equation $\ln x + \log x = 5$.
2. Here, $\ln x$ is the natural logarithm (log base $e$) and $\log x$ is the common logarithm (log base 10).
3. We use the change of base formula: $\log x = \frac{\ln x}{\ln 10}$.
4. Substitute into the equation:
$$\ln x + \frac{\ln x}{\ln 10} = 5$$
5. Factor out $\ln x$:
$$\ln x \left(1 + \frac{1}{\ln 10}\right) = 5$$
6. Simplify the factor:
$$1 + \frac{1}{\ln 10} = \frac{\ln 10 + 1}{\ln 10}$$
7. So,
$$\ln x \cdot \frac{\ln 10 + 1}{\ln 10} = 5$$
8. Solve for $\ln x$:
$$\ln x = 5 \cdot \frac{\ln 10}{\ln 10 + 1}$$
9. Calculate numerically using $\ln 10 \approx 2.302585$:
$$\ln x = 5 \cdot \frac{2.302585}{2.302585 + 1} = 5 \cdot \frac{2.302585}{3.302585} \approx 5 \cdot 0.697 = 3.485$$
10. Exponentiate both sides to solve for $x$:
$$x = e^{3.485}$$
11. Calculate $x$:
$$x \approx 32.656$$
12. Therefore, the solution is $x \approx 32.656$, which corresponds to option B.
Logarithm Solution 25E2Fe
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