Q12.Let A = {1, 2, 3, 4} and B = {1, 4, 9, 16}. Then the number of many-one functions f : A →B such that 1 ∈f( A) is equal to : (1) 151 (2) 139 (3) 163 (4) 127
What This Question Tests
This question tests the ability to count the number of many-one functions from one set to another with a specific restriction on the image, often solved using complementary counting.
Concepts Tested
Formulas Used
Number of functions from A to B is |B|^|A|
Principle of Inclusion-Exclusion
📚 NCERT Sections This Tests
12.5 — A Hydrogen Atom Initially In The Ground Level Absorbs A Photon,
Physics Class 12 · Chapter 12
12.5 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.
12.1 — (A) No Different From
Physics Class 12 · Chapter 12
12.1 (a) No different from (b) Thomson’s model; Rutherford’s model (c) Rutherford’s model (d) Thomson’s model; Rutherford’s model (e) Both the models
14.2 — Which Of The Statements Given In Exercise 14.1 Is True For P-Type
Physics Class 12 · Chapter 14
14.2 Which of the statements given in Exercise 14.1 is true for p-type semiconductos.
📋 Question Details
- Chapter
- Sets Relations Functions
- Topic
- Counting functions with restrictions
- Year
- 2025
- Shift
- 22 Jan Shift 2
- Q Number
- Q12
- Type
- MCQ
- NCERT Ref
- Class 12 Mathematics Ch 1: Relations and Functions
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