# Math Help - proof - curvature of plane curve

1. ## proof - curvature of plane curve

can someone help me with this proof- either give me advice on how to do it or get start or start me off and give a few pointers on what i should be doing..the proof is on the attachment. thanks

2. Well, what do you know about "curvature" and what formulas do you have for it? I suspect there are a number of different proofs of this starting from different formulas. You might, for example, use the fact that the curvature is $\left|\frac{dT}{ds}\right|$ where T is the unit tangent vector and s is the arclength. You would need to relate both parameters to the arclength. Then basically use the chain rule.