The position vector r(t) = <7t, 6cost, 6sint> describes the path of a particle in space. What is the particle's speed?
A. 3√7
B. √93
C. √85
D. 149
E. 21
the speed is √((dx/dt)^2 + (dy/dt)^2 + (dz/dt)^2)
...
A. 3√7
B. √93
C. √85
D. 149
E. 21
...