A4*: The non-zero elements form a group under multiplication.

Now square the graph (all non-zero elements are no positive).

In each case, one has the product formula for non-zero elements x:

An abelian group is called torsion-free if every non-zero element has infinite order.

More generally, any division algebra is a domain, since all its non-zero elements are invertible.

The non-zero elements of a finite field form a cyclic group under multiplication.

The camera matrix derived here may appear trivial in the sense that it contains very few non-zero elements.

To define them he uses diagonal matrices A having only +1 or 1 for non-zero elements.

However, it allows division of a non-zero element by zero.

Zero may be the square of some non-zero elements.