Q68.If ๐( โ, ๐) be point on the parabola ๐ฅ= 4๐ฆ2, which is nearest to the point ๐( 0, 33 ) , then the distance of ๐ from the directrix of the parabola ๐ฆ2 = 4 ( ๐ฅ+ ๐ฆ) is equal to: (1) 2 (2) 4 (3) 8 (4) 6
What This Question Tests
The problem tests finding the point on a parabola closest to a given external point using calculus (differentiation) and then calculating the distance of that point from the directrix of a different parabola.
Concepts Tested
Formulas Used
Distance = sqrt((x2-x1)^2 + (y2-y1)^2)
dD/dx = 0 for extremum
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๐ Question Details
- Chapter
- Parabola
- Topic
- Nearest point on parabola to a point
- Year
- 2023
- Shift
- 30 Jan Shift 1
- Q Number
- Q68
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 11: Conic Sections
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