Let A={1,\ 2,\ ,\ n} and B={a ,\ b} . T...

Let `A={1,\ 2,\ ,\ n}` and `B={a ,\ b}` . Then the number of subjections from `A` into `B` is `\ ^n P_2` (b) `2^n-2` (c) `2^n-1` (d) `\ ^n C_2`

A

`.^(n)P_(2)`

B

`2^(n)-2`

C

`2^(n)-1`

D

none of these

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The correct Answer is:

B

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