Okay.Originally Posted by braddy
There exists preciesly one such number such as because the real numbers form a group under addition.
Since addition is associative we have,
is an identity element we have,
Since, it is an element of the real numbers under multiplication and form a group. Thus, there exist a unique, such as, .
Since, multiplication is associative we have,
Since 1 is the multiplicative identity element we have,