Question
The binary operation × defind on set R, given by $\text{a}\times\text{b}=\frac{\text{a}+\text{b}}{2}$ for all a, b $\in$ R is:
  1. Commutative.
  2. Associative.
  3. Both (a) and (b).
  4. None of these.

Answer

  1. Commutative.

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