JEE Main 2024 · MathsMultiple choiceSingle correctMediumCalculation

JEE Main 31 January 2024, Shift 1, Maths Q3

Question 3 of 90 in this shift, Maths question 3 of 30, Section A.

f(x)=\begin{vmatrix}x^3 & 2x^2+1 & 1+3x\\ 3x^2+2 & 2x & x^3+6\\ x^3-x & 4 & x^2-2\end{vmatrix}

for all

x\in\mathbb{R}

, then

2f(0)+f'(0)

is equal to

(1) $24$
(2) $18$
(3) $42$ Official answer
(4) $48$

Official answer

Option 3

NTA final key.

Chapter: Determinants
Topic: Chain Rule
Idea tested: Chain Rule in Determinants

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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.