JEE Main2019Math
Q.
Let N be the set of natural numbers and two functions f and g be defined as
f, g : N N such that
\,f\left( n \right)\, = \left\{ {\begin{array}{*{20}{c}} {\dfrac{{n + 1}}{2}\,\,\,\,\,if\,n\,{\text{is}}\,{\text{odd}}} \\ {\dfrac{n}{2}\,\,\,\,\,if\,n\,\,{\text{is}}\,{\text{even}}} \end{array}} \right.
and g(n) = n – (–1)n. Then fog is :
- A
One-one but not onto
- B
Onto but not one-one
- C
Neither one-one nor onto
- D
Both one-one and onto
Solution
