WBJEE · Maths · Parabola
If \(P\) be a point on the parabola \(y^{2}=4 a x\) with focus \(F\). Let \(Q\) denote the foot of the perpendicular from \(P\) onto the directrix. Then, \(\frac{\tan \angle P Q F}{\tan \angle P F Q}\) is
- A 1
- B \(\frac{1}{2}\)
- C 2
- D \(\frac{1}{4}\)
Answer & Solution
Correct Answer
(A) 1
Step-by-step Solution
Detailed explanation
Equation of parabola is \[ y^{2}=4 a x \] Let the parametric coordinate of point \(P\) on the parabola is \((a, 2 a)\) Now. \(Q F=2 \sqrt{2} a\) \[ P Q=2 a \text { and } P F=2 a \] we observe that, \(O F^{2}=P Q^{2}+P F^{2}\) \(\Rightarrow \quad 8 a^{2}=4 a^{2}+4 a^{2}=8 a^{2}\)…
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