Find the domain of the vector function $\vec{r}(t)=\left\langle t^{3}, \sqrt{t+3}, \sqrt{-1-t}> \right.$ Domain: $\{t \mid \square \leq t \leq \square\}$
Hence, the domain of \(\vec{r}(t)\) is \(\boxed{[-3,-1]}\).
Step 1 :The vector function \(\vec{r}(t)=\left\langle t^{3}, \sqrt{t+3}, \sqrt{-1-t}\right\rangle\) is defined only when \(t+3\geq 0\) and \(-1-t\geq 0\).
Step 2 :From \(t+3\geq 0\), we get \(t\geq -3\).
Step 3 :From \(-1-t\geq 0\), we get \(t\leq -1\).
Step 4 :Hence, the domain of \(\vec{r}(t)\) is \(\boxed{[-3,-1]}\).