JEE Main 2026 — Matrices Question with Solution
JEE Main 2026 (23 January Shift 2)
Question
Let and be a matrix such that . Then the sum of the diagonal elements of is equal to .
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Show full solutionCorrect answer: 3
Correct answer
3
Step-by-step explanation
is skew-symmetric ().
From :
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Since is skew-symmetric, and commute:
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Trace of .
From :
.
.
Since is skew-symmetric, and commute:
.
.
Trace of .
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This is a previous-year question from JEE Main 2026, covering the Matrices chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.