JEE MATHEMATICS MCQ: FUNCTIONS

1 Easy

1 of 1

Application +4 | -1

The number of surjections from

A=\{1,2, \ldots, n\}, n \geq 2

onto

B=\{a, b\}

View answer and explanation

Correct option: B

2^n-2

Option B (

2^n-2

) is correct because it represents the total number of functions from A to B minus the functions that map all elements of A to a single element in B.

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