Maths-
General
Easy
Question
PSQ is a focal chord of a parabola whose focus is S & vertex A . PA and QA are produced to meet the directrix in R and T respectively then 
- 90º
- 60º
- 45º
- 30º
The correct answer is: 90º
To find angle
Let parabola 
Equation of TAQ = y = 
y=(-2t)x
At x=-a;
y=2at
T=(a,2at)
Equation of RAP is y=
Therefor angle 
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