Q67.If vertex of parabola is (2, −1) and equation of its directrix is 4x −3y = 21, then the length of latus rectum is (1) 2 (2) 8 (3) 12 (4) 16
What This Question Tests
This question directly applies the definition of a parabola to find the distance 'a' from the vertex to the directrix, which is then used to calculate the length of the latus rectum.
Concepts Tested
Formulas Used
Distance from point (x0, y0) to line Ax+By+C=0 is |Ax0+By0+C|/sqrt(A^2+B^2)
Length of latus rectum = 4a
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📋 Question Details
- Chapter
- Parabola
- Topic
- Properties of parabola
- Year
- 2022
- Shift
- 28 Jun Shift 2
- Q Number
- Q67
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 11: Conic Sections
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