JEE Main 2021 · MathsMultiple choiceSingle correctMediumApplication

JEE Main 18 March 2021, Shift 1, Maths Q71

Question 71 of 90 in this shift, Maths question 11 of 30, Section A.

The real valued function

f(x)=\dfrac{\mathrm{cosec}^{-1}x}{\sqrt{x-[x]}}

, where

[x]

denotes the greatest integer less than or equal to

x

, is defined for all

x

belonging to :

(1)all reals except integers
(2)all reals except the interval $[-1,1]$
(3)all non-integers except the interval $[-1,1]$ Official answer
(4)all integers except $0,-1,1$

Official answer

Option 3

NTA final key.

Chapter: Inverse Trigonometric Functions
Topic: Functions and Domain
Idea tested: Domain of Inverse Secant and Cosecant

Same topic in other shifts

All Functions and Domain questions

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.