# Help me with this..

What do you call the element aside from the identity element which when a binary operation is applied to itself the product would be the identity element? example,

                    e * e = e <-- identity element
a * a = e <-- what do you call element a?


I have been searching for the term most appropriate for it but it seems that it doesn't have one.

Note by Israel Sapnu Jr.
3 years, 4 months ago

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Idempotent

Staff - 3 years, 4 months ago

isn't it idempotent if a * a = a? i think the identity element for any group is idempotent, but what do you call element a if a * a = the identity element.

- 3 years, 4 months ago

Self inverse

Staff - 3 years, 4 months ago

is there any special name for it?

- 3 years, 4 months ago