Calculate the velocity and acceleration vectors, and speed for $$\mathbf{r}(t)=\langle \sin\!\left(t\right),\sin\!\left(4t\right),\cos\!\left(4t\right) \rangle$$ when $t=\frac{ \pi}{4}$.

Velocity:
Acceleration:
Speed:

Usage: To enter a vector, for example $\langle x,y,z\rangle$, type "$<$ x, y, z $>$"