Calculate Frenet Apparatus for Space Curve

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The discussion focuses on calculating the Frenet apparatus for the space curve defined by r(t) = ⟨t - cos(t), sin(t), t⟩. The user has derived the tangent vector T(t) but is uncertain about the correctness of their calculations, particularly regarding the magnitude of r'(t) and the subsequent steps. They seek clarification on whether to use the quotient rule for vector derivatives and express confusion about needing additional derivatives for curvature and torsion. The conversation also includes a resolution of LaTeX formatting issues. The user ultimately aims to compute the complete Frenet apparatus, including tangent, normal, binormal, curvature, and torsion.
Sneaksuit
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I need to calculate the Frenet apparatus for the space curve defined by

\overrightarrow{r} (t) = \langle t - cos (t), sin(t), t \rangle

so for T I did
\overrightarrow{r} \prime (t) = \langle 1 + sin(t), cos(t), 1 \rangle
then I got |r'(t)| = \sqrt{2sin(t) + 3
which I'm pretty sure is either wrong or not simplified. Anyone care to look at my problem?
 
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Lose the spaces in the tex tags...and the same for the closure.<br /> <br /> <br /> Daniel.
 
Sneaksuit said:
I need to calculate the Frenet apparatus for the space curve defined by

\overrightarrow{r} (t) = \langle t - \cos (t), \sin(t), t \rangle

so for T I did
\overrightarrow{r}&#039; (t) = \langle 1 + \sin(t), \cos(t), 1 \rangle
then I got |r&#039;(t)| = \sqrt{2\sin(t) + 3}
which I'm pretty sure is either wrong or not simplified. Anyone care to look at my problem?

hmmm...i can't seem to get Latex to work properly
I fixed the LaTeX, and other problems...
 
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Thanx for the latex help. Now, do u see a problem with the math?
 
Everything is okay with your exercise.


Daniel.
 
Ok, but then that gives me
T(t) = \frac{(1 + sin(t))i + (cos(t))j + k} {\sqrt{2sin(t) + 3}}
Now for T'(t) I don't ever remember taking derivatives of vectors this complicated. Do I use the quotient rule?
 
Okay,that's r' vector which is indeed the tangent vector.Now why would you need another derivative wrt to "t"...?Curvature,torsion...?

Daniel.
 
Yes, I need the entire Frenet apparatus...tangent, normal, binormal, curvature, and torsion.
 
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