Hello everyone, the problem says to:(adsbygoogle = window.adsbygoogle || []).push({});

For the curve gien by r(t) = <1/3* t^3, 1/2 * t^2, t>

find (a) The unit tagent vector;

(b) the unit normal vector;

(c) the curvature;

Well it seems easy enough! the formula's are just derivatives for instance:

The unit tagent vector says:

T(t) = r'(t)/|r'(t)| i got this one right, you can see my work on the image below:

but part (b) i missed..

The normal vector N is suppose to just be:

N(t) = T'(t)/|T'(t)|;

Here is my work and it does not match the back of the book.

http://show.imagehosting.us/show/800636/0/nouser_800/T0_-1_800636.jpg

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# Homework Help: Finding the unit tagent vector, normal vec and curvature problem

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