MCQ
The identity element for the binary operation $\times $ defined on $Q - \{0\}$ as $\text{a}\times\text{b}=\frac{\text{ab}}{2}\ \forall a, b \in Q - \{0\}$ is:
  • A
    $1$
  • B
    $0$
  • $2$
  • D
    None of these.

Answer

Correct option: C.
$2$

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