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JEE Main 2017 · MathsMultiple choiceSingle correctMediumCalculation

JEE Main 2 April 2017 (offline), Maths Q64

Question 64 of 90 in this shift, Maths question 4 of 30.

If

A=\begin{bmatrix}2&-3\\-4&1\end{bmatrix}

, then

\mathrm{adj}(3A^2+12A)

is equal to :

(1) $\begin{bmatrix}51&63\\84&72\end{bmatrix}$ Official answer
(2) $\begin{bmatrix}51&84\\63&72\end{bmatrix}$
(3) $\begin{bmatrix}72&-63\\-84&51\end{bmatrix}$
(4) $\begin{bmatrix}72&-84\\-63&51\end{bmatrix}$

Official answer

Option 1

CBSE answer key (25/04/2017, used for result).

Chapter: Determinants
Topic: Matrix Inverse
Idea tested: Cofactor Matrix and Adjoint

Same idea in other shifts

Asked 2× in all

8 Apr 2026, Shift 2 · Q4Let $A = \begin{bmatrix} \alpha & 1 & 2 \\ 2 & 3 & 0 \\ 0 & 4 & 5 \end{bmatrix}$ and…HardSingle correct

Question text from the official JEE Main paper published by NTA (CBSE ran the 2017 exam); 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.