Hello,

i have a question to this exercise:

Show that the surface of revolution defined by this curve is a submanifold:

g: ,

I could show, that this surface is a regular 2-dimensional submanifold.

Because the derivative of the parametrisation of the surface has at any point dimension 2.

But now i ask myself what about the smoothness of my submanifold? Is it a

surface? or only a . How can i decide about this question.

I hope you can help me in my problem.

Regards