CA Foundation P3 · Chapter 7 · Question 9 of 9
If A has 3 elements and B has 5 elements, the number of one-one functions from A to B is:
Test yourself: pick an answer
Reveal answer & explanation
Correct answer: C) 60
Explanation
A one-one function assigns distinct images to the 3 elements of A: 5 choices for the first, 4 for the second and 3 for the third, i.e. ⁵P₃ = 60. The total number of functions is 5³ = 125, 3⁵ = 243 reverses domain and co-domain, and ⁵C₃ = 10 ignores order.
More Sets, Relations and Functions, Basics of Limits and Continuity of Functions MCQs
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- Q3The relation R = {(1, 1), (2, 2), (3, 3), (1, 2)} on the set {1, 2, 3} is:
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