AIEEE 2008 (Offline)Question 1
Let $f:N\to Y$ be a function defined as $f(x)=4x+3$ where $Y=\{y\in N,\ y=4x+3\text{ for some }x\in N\}$. Show that $f$ is invertible and its inverse is
Functions
Solution
$f$ is one-one and onto $Y$; $y=4x+3\Rightarrow x=\frac{y-3}{4}$, so $g(y)=\frac{y-3}{4}$.