Question

The number of bijective functions from the set $A$ to itself, if $A$ contains $108$ elements is -

• A. $180$
• B. $(180)!$
• C. $(108{)}^{!}$
• D. $2^{108}$

Answer 1

Answer: (C)

Since number of one-one onto functions from a set A having n elements to itself is n!.
We have the set A that contains 108 elements, so the number of bijective functions from set A to itself is 108!