Q70.If one end of a focal chord of the parabola, y2 = 16x is at (1, 4), then the length of this focal chord is (1) 24 (2) 25 (3) 22 (4) 20 , then a value of m is:
What This Question Tests
The problem involves identifying the parameter 'a' of the parabola and using the coordinates of one end of the focal chord to find the parameter 't'. The length of the focal chord can then be directly calculated using its formula.
Concepts Tested
Formulas Used
For y²=4ax, focus is (a,0) and a point on parabola is (at², 2at)
Length of focal chord = a(t + 1/t)²
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📋 Question Details
- Chapter
- Parabola
- Topic
- Focal chord of a parabola
- Year
- 2019
- Shift
- 09 Apr Shift 1
- Q Number
- Q70
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 11: Conic Sections
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