Same chapter3 marksDifficulty: Medium
Find the area of the triangle with vertices (1, 2), (4, 6) and (−2, 3) using determinants.
Determinants
3 marksDifficulty: Medium
State the condition on the determinant of the coefficient matrix for a system of linear equations to have a unique solution.
Original Khojo Papers practice question — not from a past board paper.
Answer
A system AX = B has a unique solution when the determinant of A is non-zero, so that A is invertible and X = A−1B. If the determinant is zero the system has either no solution or infinitely many.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Which of the two applies is decided by whether (adj A)B is zero.
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