WBJEE · Maths · Parabola
If \(P_1 P_2\) and \(P_3 P_4\) are two focal chords of the parabola \(y^2=4 a x\) then the chords \(P_1 P_3\) and \(P_2 P_4\) intersect on the
- A directrix of the parabola
- B axis of the parabola
- C latus-rectum of the parabola
- D \(y\)-axis
Answer & Solution
Correct Answer
(A) directrix of the parabola
Step-by-step Solution
Detailed explanation
Let \(P_i\left(a_i{ }^2, 2 a t_i\right), i=1,2,3,4\) then, \(t_1 t_2=t_3 t_4=-1\) equation of \(P_1 P_3\) : \(\left(t_1+t_3\right) y=2 x+2 a t_1 t_3\) ...(1) \(P_2 P_4:\left(t_2+t_4\right) y=2 x+2 a t_2 t_4\) ...(2) Putting \(x=-a\) in equation (1) gives…
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