AP EAPCET 04-Jul-2022 Shift 1 Paper

Focus ≡(0,0)
Tangent at vertex of parabola: x−y+1=0
The distance between the focus and tangent at the
‌ vertex ‌=|‌

0−0+1

√12+12

|=‌

1

√2

The directrix is the line parallel to the tangent at vertex and at a distance 2×‌

1

√2

from focus.
Let the equation of directrix be
x−y+λ=0
Here, ‌

λ

√12+12

=‌

2

√2

⇒‌‌λ=2
∴ Equation of directrix is x−y+2=0