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Binary Operations — Maths STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceMathsBinary Operations1 Mark
MCQ
The number of commutative binary operation that can be defined on a set of 2 elements is:
  • A
    8
  • B
    6
  • C
    4
  • ✓
    2
✓

Answer

Correct option: D.
2
The number of commutative binary operations on a set of n elements is $\text{n}\frac{\text{n}(\text{n}-1)}{2}$.

Therefore,

Number of commutative binary operations an a set of 2 elements $=2\frac{2(2-1)}{2}=2^1$

$=2$

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