JEE Main 2020 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 9 January 2020, Shift 2, Maths Q58

Question 58 of 75 in this shift, Maths question 8 of 25, Section A.

Let

[t]

denote the greatest integer

\le t

and

\lim_{x\to0}x\left[\frac{4}{x}\right]=A

. Then the function,

f(x)=[x^2]\sin(\pi x)

is discontinuous, when

x

is equal to :

(1) $\sqrt{A}$
(2) $\sqrt{A+1}$ Official answer
(3) $\sqrt{A+5}$
(4) $\sqrt{A+21}$

Official answer

Option 2

NTA final key (Jan 2020).

Chapter: Continuity and Differentiability
Topic: Continuity and Differentiability
Idea tested: Continuity involving GIF and Fractional Part

Same idea in other shifts

Asked 7× in all

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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.