# Calc 3 curvature verification

1. Oct 19, 2014

### nate9519

1. The problem statement, all variables and given/known data
verify that |T ' (s)| = |T ' (t)| / |r ' (t)|

2. Relevant equations
K = |dT / ds|

K = |r'(t) x r''(t)| / |r'(t)|^3 the x is a cross product

3. The attempt at a solution
I don't know how to start this problem because one side of the verification is in terms of arc length and the other side is in terms of time. Could some one help me get the ball rolling and explain how I get both sides in terms of the same parameter

2. Oct 19, 2014

### LCKurtz

Your relevant equations aren't relevant. Use the chain rule to get $T'(s)$ in terms of $t$.