Determine whether or not each of the definition of given below gives a binary operation. In the event that is not a binary operation, give justification for this.

On Z+, define by a b = a – b


It is given that On Z+, define by a b = a – b

It is not a binary operation as the image of (1, 2) under * is


1 * 2 = 1 – 2 = -1 Z+.


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