Expanding: 1(5k-48) - 2(4k-42) + 3(32-35) = 0. Solving: k = 9.
Back to JEE Main 2020 Algebra
JEE Main 2020 — Mathematics Algebra
medium
mcq
2020
Official previous-year question
Verified 30 May 2026.
Question
If the determinant |1 2 3; 4 5 6; 7 8 k| = 0, then k equals:
Options
- A6
- B9
- C12
- D15
Solution
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