Are all identity Matrices square matrices?

yes all identity Matrices s are quare matrices

Among other things, an identity matrix is one which, when multiplying another matrix, leaves it unchanged (this is a requirement by definition -- if it does not do this, it is not an identity matrix).

A 3x2 matrix, when multiplying a 3x2 matrix, will either turn it into a 2x2 matrix or a 3x3 matrix (depending if it is "right-multiplied" or left-multiplied).

Taking a 3x2 matrix and changing it into a 2x2 matrix is definitely not "leaving it unchanged".

among countless issues, an identity matrix is one that, while multiplying one extra matrix, leaves it unchanged (it quite is in many circumstances a call for by capacity of utilising definition -- if it does not try this, it is not an identity matrix). A 3x2 matrix, while multiplying a 3x2 matrix, will the two turn it right into a 2x2 matrix or a 3x3 matrix (based no be counted if it extremely is "superb-more advantageous" or left-greater). Taking a 3x2 matrix and changing it superb right into a 2x2 matrix is not any doubt no longer "leaving it unchanged".

ya of course it will be always a square matrix..so 3x2 matrix is not possible anyway.

http://en.wikipedia.org/wiki/Identity_matrix

http://mathworld.wolfram.com/IdentityMatrix.html