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# 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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