1. calculate the length of the following paths:(adsbygoogle = window.adsbygoogle || []).push({});

f(t) = (7, t, t^2) over 1<t<3

the way i was taught in class to calculate the length of a curve is to integrate the magnitude of the velocity, but i cant seem to naturally integrate the magnitude of (0, 1, 2t)

similarly for:

f(t) = (cos(3t), sin(3t), 2t^(3/2)) 0<t<4

2. prove the bac-cab formula

aX(bXc) = b(a*c) - c(a*b)

where * is the dot product

what does b(a*c) mean?! how do i evaluate that?

i wrote aX(bXc) in terms of the component form, etc.

3. prove the length curve and curvature formulas.

5. prove aX(bXc) = (aXb)Xc + bX(aXc)

PLEASE HELP!

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# Homework Help: Ugh, so lost on this calc 3 homework PLEASE HELP!PLEASE HELP!PLEASE HELP!PLEASE HELP!

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