Originally Posted by

**Beevo** Hey everyone,

I am having a bit of difficulty solving this problem. It says:

A particle has position function $\displaystyle \ r(t) = (2\sqrt{2})i + (e^{2t})j + (e^{-2t})k$. What is its speed at time t?

Well I first took the derivative of the function. Then I took the magnitude to find the length which corresponds to the speed. I got my answer to be

$\displaystyle \sqrt{8+4e^{2t}+4e^{-2t}}$, is this answer correct? If so, how would I further simplify it? If it is incorrect, what am I doing wrong?

Any help and feedback is greatly appreciated, thanks.