clearly not. a^2/a = a

Question

But that is not what you had.
Also, you do in fact need to check a_3/a_2

Is it a/2 or -a/2? I think it is a/2

Answer 1

yes, it is -a/2
But you do need to check a_3/a_2. It is clearly not the same.

and try to ask follow-up questions in the same post, rather than start what looks like a new question. Someone who had not seen your earlier post would have no idea what you're talking about here.