Thank you for confirming the fact that the Church does not and has not taught that the Earth is flat.

Stubborn heliocentrics defy the Church and simple logic.

Lucky for you, someone has recently been to the "edge" and has seen where the dome meets the earth.  Cosmas of Indiocopleustes and other explorers also explain exactly what it looks like which is identical to the Encyclopedia.  So, while I haven't been there, others have and described it for us.      

I cannot locate that video on youtube, I scrolled through all of his vids and didn't see it.  I did see 4 other videos by other youtubers and all referenced back to a woman reading that same passage, I assume those are re-uploads.  
I would think that there are enough flat-earth/geocentrics who could donate to a go-fund-me page dedicated to raising money for an independent expedition to the end of the earth.  Such an expedition could certainly put an end to the speculation and tossing about of conspiracy theories.

Where has the Church taught that the earth is a sphere?

Well it's you who keeps asking.

In any case, whether it is a teaching is a red herring.

The important thing is that it is scientific. We can't deny our senses without being fools.

Well it's you who keeps asking.

In any case, whether it is a teaching is a red herring.

The important thing is that it is scientific. We can't deny our senses without being fools.

Thank you.  We agree then that the Church does not teach that the Earth is flat.  Good, so now we can review the science.  

We're not agreeing on anything in relation to the above. I just said it was a red herring.

As for your maths, it is nothing but the imposition of spherical trigonometry on two points on our flat earth. It makes the presupposition that the earth is round and then imposes this trigonometry on it.

But that is completely ridiculous. It is a nice mathematical abstraction, but doesn't prove the earth to be round. It presumes it.