Question:
If the midpoints of sides BC, CA, AB of triangle ABC are respectively D, E, F, then position vector of centre of triangle DEF, when position vectors of A, B, C are respectively i+ j, j+ k, k+ i, is
If the midpoints of sides BC, CA, AB of triangle ABC are respectively D, E, F, then position vector of centre of triangle DEF, when position vectors of A, B, C are respectively i+ j, j+ k, k+ i, is
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Centroid of medial triangle equals centroid of original triangle.
Updated On: Mar 18, 2026
- \frac13( i+ j+ k)
- ( i+ j+ k)
- 2( i+ j+ k)
- \frac23( i+ j+ k)
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Verified By Collegedunia
The Correct Option is D
Solution and Explanation
Step 1: Position vector of centroid remains same for medial triangle.
Step 2: (A+B+C)/(3)=\frac23( i+ j+ k)
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