Set A has 3 elements and set B has 4 elements. The number of injection...
To find the number of injections (one-to-one mappings) from set A to set B, we can use the concept of permutations.
Permutations:
A permutation is an arrangement of objects in a specific order. In this case, we want to find the number of permutations of set B, where each element of set A is mapped to a distinct element in set B.
Formula for Permutations:
The number of permutations of a set with n elements is given by n!, which is the factorial of n. Factorial means multiplying all positive integers from 1 to n.
Number of Elements in Sets A and B:
Given that set A has 3 elements and set B has 4 elements.
Calculating the Number of Permutations:
To find the number of injections from A to B, we need to calculate the number of permutations of the 4-element set B, taking 3 elements at a time. This is denoted as P(4,3).
Using the formula for permutations, we have:
P(4,3) = 4!
= 4 × 3 × 2 × 1
= 24
Therefore, the number of injections that can be defined from set A to set B is 24.
Answer:
Hence, the correct answer is option 'D' (24).
Set A has 3 elements and set B has 4 elements. The number of injection...
No. of injections = 4P3 = 24