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u are at the origin and want to hike to point (4pie,0,0). U want to get to 4pie,0,0 by hiking a route that alway keeps you at the same elevation. what is the lenght of this route?

I ploted the graph and I already know the route that will keep me at the same elevation from origin to 4pie,0,0 but how do I find the lenght of that route??

As for the second part

Your second route always moves along the gradient. Determine such a route of minimal lenght, assuming you start hiking in the positive x direction. What is the length? If you cannot find and exact answer, then determine an upper bound and a lower bound bbetween which the actual lenght must lie.

I have no clue on doing the second part.

I need some serious help because this will determine my final grade so be clear and help me as much as u can. Thanks

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# Homework Help: Need with 3d graph question

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