MCQ
In set-builder method the null set is represented by:
  • A
    $\{\}$
  • B
    $\phi$
  • $\{\text{x : x} \not=\text{x}\}$
  • D
    $\{\text{x : x} =\text{x}\}.$

Answer

Correct option: C.
$\{\text{x : x} \not=\text{x}\}$
  1. $\{\text{x : x}\not=\text{x}\}.$

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