JEE Main 2021 · MathsMultiple choiceSingle correctMediumApplication

JEE Main 31 August 2021, Shift 1, Maths Q69

Question 69 of 90 in this shift, Maths question 9 of 30, Section A.

The function

f(x)=|x^2-2x-3|\cdot\mathrm{e}^{|9x^2-12x+4|}

is not differentiable at exactly :

(1)one point
(2)two pointsOfficial answer
(3)three points
(4)four points

Official answer

Option 2

NTA final key.

Chapter: Continuity and Differentiability
Topic: Continuity and Differentiability
Idea tested: Differentiability of Modulus Functions

Same idea in other shifts

Asked 9× 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 108 of the 174 JEE Main shifts held from 2017 to 2026.