MCQ
Set $A$ has $3$ elements and set $B$ has $4$ elements. The number of injection that can be defined from $A$ to $B$ is
  • A
    $144$
  • B
    $12$
  • $24$
  • D
    $64$

Answer

Correct option: C.
$24$
c
(c) The total number of injective functions from a set $A$ containing $3$ elements to a set $B$ containing $4$ elements is equal to the total number of arrangements of $4$ by taking $3$ at a time $i.e.,$  $^4{P_3} = 24$.

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