(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I'm trying to find a surface of revolution with Gauss curvature K of +1 at all points, which doesn't lie in a sphere.

2. Relevant equations

The surface is parametrized as [itex]\psi (t, \theta ) = ( x(t), y(t) cos \theta , y(t) sin \theta ) [/itex]

I have the equation

[tex]

K = \frac{x' (x'' y' - x' y'')}{y(x'^2 + y'^2)^2}

[/tex]

3. The attempt at a solution

I am thinking it has to do with the curve [itex] \alpha (t) = (x(t),y(t)) [/itex] not having unit speed, but I am kind of stuck as to where to go from there.

Thanks!

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# Homework Help: Surface of constant curvature

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