What's the length of the curve?

Question

What's the length of the curve r(t)=<2 cos t, 2 sin t, sqrt(5)> from 0<=t<=2pi?

Answer 1

Integral of the length of a curve in three dimensions is integral over time of sqrt((dx/dt)^2+(dy/dt)^2+(dz/dt)^2). Can you take the derivative of each?