$\huge \int_{0}^{1} 10^x \d x $ $\huge \begin{align} \int 10^x \d x &= \frac{10^{x}}{\ln 10} \\ \int_{0}^{1} 10^x \d x &= \frac{10^{1}}{\ln 10} - \frac{10^{0}}{\ln 10}\\ &= \frac{9}{\ln 10} \end{align} $