Chapter 11 - Section 11.5 - Derivatives of Logarithmic and Exponential Functions - Exercises - Page 842: 33

$ \displaystyle \frac{2.6}{x-1}$

Apply the power rule for logarithms $s(x)=1.3\ln(4x-2)$ Apply $\displaystyle \frac{d}{dx}[\ln|u|]=\frac{1}{u}\cdot\frac{du}{dx}$, with constant multiple, $r^{\prime}(x)=1.3\displaystyle \cdot\frac{1}{4x-2}\cdot 4=$ $=1.3\displaystyle \cdot\frac{1}{2(x-1)}\cdot 4$ $=\displaystyle \frac{2.6}{x-1}$