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Matrices & Determinants

JEE Main level, single correct, medium

1 of 3

Question 1 of 3

If the matrix $A = \begin{pmatrix} 2 & k \\ 4 & 6 \end{pmatrix}$ is singular, then the value of $k$ is:

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Answer: (D) 3

For a singular matrix,

\det(A) = 0 \implies 2(6) - 4k = 0 \implies 12 = 4k \implies k = 3

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JEE Main 2025 Apr 2 Shift 1 question paper

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JEE Main Mathematics practice question on Matrices & Determinants, with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.

If the matrix A=(2k46)A = \begin{pmatrix} 2 & k \\ 4 & 6 \end{pmatrix}A=(24​k6​) is singular, then the value of kkk is:

JEE Main question paper PDF

More Mathematics practice

If the matrix $A = \begin{pmatrix} 2 & k \\ 4 & 6 \end{pmatrix}$ is singular, then the value of $k$ is: