Q. 525.0( 1 Vote )
Mark the correct alternative in each of the following:
Let A = {1, 2, …, n} and B = {a, b}. Then the number of subjections from A into B is
A. nP2
B. 2n – 2
C. 0
D. none of these
Answer :
Given that A = {1, 2, …, n} and B = {a, b}
The number of functions from a set with n number of elements into a set of 2 number of elements = 2n
But two functions can be many-one into functions.
Hence, answer is 2n – 2.
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