1.

Determine whether each of the following operations define a binary operation on the given set or not: ‘*’ on N defined by a * b = ab for all a,b N.

Answer»

Given that ‘*’ is an operation that is valid in the Natural Numbers ‘N’ and it is defined as given: 

⇒ a*b = ab, where a,b∈N 

Since a∈N and b∈N, 

According to the problem it is given that on applying the operation ‘*’ for two given natural numbers it gives a natural number as a result of the operation,

⇒ a*b∈N ...... (1) 

We also know that pq>0 if p>0 and q>0. 

So, we can state that,

⇒ ab>0 

⇒ ab∈N ...... (2) 

From (1) and (2) we can see that both L.H.S and R.H.S gave only Natural numbers as a result. 

Thus we can clearly state that ‘*’ is a Binary Operation on ‘N’.



Discussion

No Comment Found

Related InterviewSolutions