Chapter 27, Problem 80PQ

To determine

Show that equation $V_C={\displaystyle \underset{r_{+}}{\overset{r_{-}}{\int }}Edr}$ is derived form $\begin{array}{c}\Delta V=V_f-V_i\\ =-{\displaystyle \underset{r_i}{\overset{r_f}{\int }}\overrightarrow{E}\cdot d\overrightarrow{r}}\end{array}$.