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Feb 12 2015 10:16pm
Hey sorry for another thread but I just did this question and am not very sure about my answer...



So I get this as the arc length function



Not very pretty... anyway on part b it asks me to reparametrize by arc length so I solve for t in terms of s. As you can tell it ends up even uglier. There's not much simplifying either (only in the radius), the things inside cost and sint are really bad. I was just wondering if I should expect for things to simplify nicely with this reparametrization, or is there something I am missing or doing wrong?

Any insight would be appreciated, thanks!
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Feb 12 2015 10:49pm
i dont think it will simplify any further.

rearranging gives

t = -ln[-bs/(a*sqrt(b^2+1)) + 1 ]/b which as u said is really ugly to work with.

but when u calculate curvature, i would recommend making a sub for -b/(a*sqrt(b^2+1)) = c since they r constants
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Feb 12 2015 10:55pm
Quote (2wo1ne @ Feb 12 2015 11:49pm)
i dont think it will simplify any further.

rearranging gives

t = -ln[-bs/(a*sqrt(b^2+1)) + 1 ]/b which as u said is really ugly to work with.

but when u calculate curvature, i would recommend making a sub for -b/(a*sqrt(b^2+1)) = c since they r constants


Okay just making sure, thanks
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