Anyone around familiar with set theory and isomorphisms? I'd like to check a result.
Or linear algebra, for that matter? I don't remember it all that well.
Off-topic discussion. Wanna talk about corsets, duct tape, or physics? This is the place. Detailed discussion of any current-season TV must be whitefonted.
Anyone around familiar with set theory and isomorphisms? I'd like to check a result.
Or linear algebra, for that matter? I don't remember it all that well.
Emily, I'm here, for another few minutes at least.
Ooh! Excellent! So tell me, is phi(A)=det(A) an isomorphism from the structure (2x2 matrices, +) to the structure (Reals, +)? It seems to me like it's not one-to-one, but I did want to be sure.
I will have other questions, mwahahah.
So tell me, is phi(A)=det(A) an isomorphism from the structure (2x2 matrices, +) to the structure (Reals, +)? It seems to me like it's not one-to-one, but I did want to be sure.
It's not an isomorphism. You're right, it's not one-to-one; as a trivial example, any matrix where all four entries are the same will map to 0.
Lily is so beautiful. She often appears to have an air of slumming royalty, amused at the antics of the little people.
I have an odd urge to make snickerdoodles, but am too lazy to look up a recipe and figure out if I have all the ingredients.
Diagonal matrices are invertible, right?
Diagonal matrices are invertible, right?
Right.
I need somebody to take me out to the store, yet I am too lazy to actually call anybody with a car. Besides, they might turn me down. So I may well die of hunger before long.
I'd take you, Theodosia, if I weren't dedicated to being slug like.