Chapter 11 - Vectors and Vector-Valued Functions - 11.6 Calculus of Vector-Valued Functions - 11.6 Exercises - Page 814: 12

$\textbf{r}'(t) = \langle sec^2(t), sec(t)tan(t), -2sin(t)cos(t)\rangle$

$\textbf{r}(t) = \langle f(t), g(t), h(t)\rangle$ $\textbf{r}'(t) = \langle f'(t), g'(t), h'(t)\rangle$ $\textbf{r}(t) = \langle tan(t), sec(t), cos^2(t)\rangle$ $\textbf{r}'(t) = \langle sec^2(t), sec(t)tan(t), -2sin(t)cos(t)\rangle$