I am going to study mathematics

Fuck yes, I am going to study mathematics, finally.
The first semester starts october 25th, it's late due to pandemic.
Classes will be online until they aren't.

>>23
>for which it's true that all of its non null elements are invertible.
Invertible with respect to which operation? You are probably talking about the multiplicative inverse, but then you would have to talk about the definition of a product on the R^3 for your claim to make sense.