shortest chord...........

The shortest normal chord of the parabola y² = 4ax is

a) √3a
(b) 2 √3 a
(c) 3 √3 a
(d) 6√ 3 a

2 Answers

TAKE GENERAL POINT (at²,2at)

find dydx at this point
then slope of normal =- dxdy

then find equation of normal----
suppose it again intersect at
(at²₁,2at₁)

find the condition between t and t₁

find length of chord =L

then find dLdt

i think u should atleast try now...........

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