How to Verify Curvature Equation Using Chain Rule

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    Calc 3 Curvature
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Homework Statement


verify that |T ' (s)| = |T ' (t)| / |r ' (t)|

Homework Equations


K = |dT / ds|

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

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
 
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nate9519 said:

Homework Statement


verify that |T ' (s)| = |T ' (t)| / |r ' (t)|

Homework Equations


K = |dT / ds|

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

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

Your relevant equations aren't relevant. Use the chain rule to get ##T'(s)## in terms of ##t##.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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