The number of functions f:{1,2,3,4}→{a,b,c}, which are not onto, is :
(A)48
(B)45✓ Correct
(C)51
(D)35
Answer: (B)
Solution
The total number of functions from a 4-element set to a 3-element set is 34=81. By inclusion-exclusion the number of onto functions is 34−(13)24+(23)14=81−48+3=36. Hence the number that are not onto is 81−36=45.
JEE Main · 2026 · 04 Apr 2026 · Shift 1 · Single correct option