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RELATIONS AND FUNCTIONS — MATHS STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceMATHSRELATIONS AND FUNCTIONS1 Mark
MCQ
Set $A$ has $3$ elements, and set $B$ has $4$ elements. Then the number of injective mappings that can be defined from $A$ to $B$ is:
  • ✓
    $24$
  • B
    $12$
  • C
    $64$
  • D
    $144$
✓

Answer

Correct option: A.
$24$
The total number of injective mappings from the set containing $3$ elements into the set containing $4$ elements is $^4P_3 = 4! = 4 \times 3 \times 2 \times 1 = 24$.

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