Chapter 12 - Vector-Valued Functions - 12.1 Exercises - Page 822: 70

\begin{array}{l}{\mathbf{r}(t)}{\text { is continuous on }[1, \infty)}\end{array}

Given$$\mathbf{r}(t)=\sqrt{t} \ \mathbf{i}+\sqrt{t-1} \ \mathbf{j}$$ Since we have $\sqrt{t} $, which is Continuous at $t\geq0$ and $ \sqrt{t-1} $ is continuous at $t\geq1$, we find: \begin{array}{l}{\mathbf{r}(t)}{\text { is continuous on }[1, \infty)}\end{array}