#how do I start this? I tried brute forcing y' and that wasn't going well.

10 messages · Page 1 of 1 (latest)

woven rain
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Was there something else I needed to do first?

stable krakenBOT
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warm olive
# woven rain Was there something else I needed to do first?

You can do this in cartesian coordinates, in which case:
dl = √(1 + (dy/dx)^2)dx
Or you can do it by parametrizing the astroid. Then:
dl = √((dx/dt)^2 + (dy/dt)^2)dt
I recommend the second approach, as the first one leads to an integral that's solvable exactly, but quite long.
In any case, find the length of a quarter of the astroid in the first quadrant, then multiply the result by 4.

bitter marlin
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parametrise, indeed

woven rain
warm olive
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Well, as you want. The first approach might take a while, though.

little marsh
woven rain
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Yeah I'm still a tad confused

woven rain
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+close