JEE Main 2022 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 24 June 2022, Shift 2, Maths Q20

Question 20 of 90 in this shift, Maths question 20 of 30, Section A.

Let

\lambda^*

be the largest value of

\lambda

for which the function

f_\lambda(x) = 4\lambda x^3 - 36\lambda x^2 + 36x + 48

is increasing for all

x \in \mathbb{R}

. Then

f_{\lambda^*}(1) + f_{\lambda^*}(-1)

is equal to :

(1)36
(2)48
(3)64
(4)72Official answer

Official answer

Option 4

NTA final key.

Chapter: Application of Derivatives
Topic: Monotonicity
Idea tested: Parameter Range for Global Monotonicity

Same topic in other shifts

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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.