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
Show that the points (1, 2), (3, 6) and (5, 10) are collinear using a determinant.
Original Khojo Papers practice question — not from a past board paper.
Answer
The determinant of [[1, 2, 1], [3, 6, 1], [5, 10, 1]] is zero, so the area of the triangle is zero and the points are collinear.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Expanding gives 1(6 − 10) − 2(3 − 5) + 1(30 − 30) = −4 + 4 + 0 = 0.
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