Q64.Let the centroid of an equilateral triangle ABC be at the origin. Let one of the sides of the equilateral triangle be along the straight line x + y = 3. If R and r be the radius of circumcircle and incircle respectively of ΔABC , then (R + r) is equal to : (1) 9 (2) 7√2 √2 (3) 2√2 (4) 3√2
What This Question Tests
This question tests the application of coordinate geometry to find the inradius and circumradius of an equilateral triangle given its centroid and the equation of one side.
Concepts Tested
Formulas Used
r = |Ax_1 + By_1 + C| / sqrt(A^2 + B^2)
R = 2r
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📋 Question Details
- Chapter
- Coordinate Geometry
- Topic
- Straight Lines
- Year
- 2021
- Shift
- 18 Mar Shift 2
- Q Number
- Q64
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 10: Straight Lines
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