There is an operation on a set (real numbers) such that:
Does have an identity element with respect to operation ?
Now I find the identity element like this:
Is this a valid identity element for this operation?
Because an identity element has a property that it doesn't change the original element when used with the operation on set .
can be The original element is modified.
But it's also possible that . The original element is left untouched. I'm confused by these two situations.
So my question is:
Is this a valid identity element of with respect to ?