Hi
There is any generic mathematical expression (formula) to represent a Matrix squared ?
I search it before, but i didn't find.
thanks
Hi There is any generic mathematical expression (formula) to represent a Matrix squared ? I search it before, but i didn't find. thanks 

closed as too localized by Jacques Carette, Bill Johnson, Qiaochu Yuan, Will Jagy, Suvrit Nov 18 '11 at 20:46This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center. If this question can be reworded to fit the rules in the help center, please edit the question. 


If your question is to be interpreted as asking for the image of the squaring map for square matrices of a given size n over a given field: then the only superficially obvious condition is that the determinant should be a square. Over the complex number field "almost all" square matrices are squares; but it is not true in general that all matrices are squares. That is something you can read off from the Jordan normal form. I suppose that one can use abstract algebraic geometry to claim that the matrices that are squares are a constructible set. This gives one some idea that there is reasonable answer for a given n. But it may not be very useful. 

