Chapter 4, Problem 8T

To determine

To fill: The blank in the statement “If f is ______ on $\left[a,b\right]$ and $u\left(x\right)$ is ______ on $\left[a,b\right]$ , then for all $x\in \left[a,b\right]$ , $\frac{d}{dx}{\displaystyle \underset{a}{\overset{u\left(x\right)}{\int }}f\left(t\right)dt=}$______ .”