Verified Solution • 2025–26 Session moderate

QJEEM19Ma9f31: JEE Main 2019 Mathematics - Class 11 JEEM19Ma9f31 Solution: Let a function f : (0, ) (0, ) be defined by f(x) = . Then f is :

Let a function f : (0, ∞\infty ) →\to (0, ∞\infty ) be defined by f(x) = ∣1−1x∣\left| {1 - {1 \over x}} \right| . Then f is :

Multiple Choice Options

  • A not injective but it is surjective
  • B neiter injective nor surjective
  • C injective only
  • D both injective as well as surjective

Step-by-Step Verified Solution

f(x)=|1−1x|=|x−1|x={1−xx0<x≤1x−1xx≥1

JEE Main 2019 (Online) 11th January Evening Slot Mathematics - Functions Question 118 English Explanation
⇒\Rightarrow   f(x) is not injective

but range of function is [0,∞)\left[ {0,\infty } \right)

Remarks :  If co-domain is [0,∞)\left[ {0,\infty } \right) , then f(x) will be surjective.

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