Let A = 1,2,3,....,10 and f:A → A be defined as f(k) = \ k + 1 if k is odd k if k is even. Then the number of possible functions g:A → A such that gof = f is:

Sets, Relations and Functions: JEE Main 2021 Mathematics question

JEE Main 2021 · 26 Feb, Evening shift · Q3803

JEE Main 202126 Feb, Evening shiftMathematicsHardSets, Relations and Functions168× since 2002

Let

A = \{ 1,2,3,....,10\}

and

f:A \to A

be defined as

f(k) = \left\{ {\matrix{ {k + 1} & {if\,k\,is\,odd} \cr k & {if\,k\,is\,even} \cr } } \right.

Then the number of possible functions

g:A \to A

such that

gof = f

is :