# How do you integrate 10^x dx from 1 to 0?

I would do, using fundamental integration/derivation techniques, like this (from $1$ to $0$):
${\int}_{1}^{0} \left({10}^{x}\right) \mathrm{dx} = {10}^{x} / \ln \left(10\right) {|}_{1}^{0} = \frac{1}{\ln} \left(10\right) - \frac{10}{\ln} \left(10\right) = - \frac{9}{\ln} \left(10\right)$