Q39 / 90 · JEE Main 2019 (11 Jan Shift 2) · Mathematics
Let a function $f:(0, \infty) \rightarrow(0, \infty)$ be defined by
$f(x)=\left|1-\frac{1}{x}\right| .$ Then $f$ is :
- Anot injective but it is surjective
- Binjective only
- Cneither injective nor surjective
- Correct answerDNone of the above
Solution
$f:(0, \infty) \rightarrow(0, \infty)$
$f(x)=\left|1-\frac{1}{x}\right|$ is not a function
$\because f(1)=0$ and $1 \in$ domain but $0 \notin$ co-domain
Hence, $f(x)$ is not a function.
Hence, the correct answer is option: 'D'.