JEE Main 2021 · MathsNumerical answerNumerical valueHardMulti-step

JEE Main 25 February 2021, Shift 1, Maths Q87

Question 87 of 90 in this shift, Maths question 27 of 30, Section B.

Let

f(x)

be a polynomial of degree 6 in

x

, in which the coefficient of

x^6

is unity and it has extrema at

x = -1

and

x = 1

. If

\lim_{x \to 0} \frac{f(x)}{x^3} = 1

, then

5 \cdot f(2)

is equal to __________.

Official answer

144

NTA final key.

Chapter: Application of Derivatives
Topic: Maxima and Minima
Idea tested: Critical vs Stationary Points

Same idea in other shifts

Asked 3× in all

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9 Apr 2024, Shift 2 · Q25Let the set of all values of $p$ , for which $f(x)=(p^2-6p+8)\left(\sin^2 2x-\cos^2 2x\right)+2(2-p)x+7$ does not have any critical point,…MediumNumerical value

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.