Question
Question: The angle between the normals to the parabola y<sup>2</sup> = 24x at the points (6, 12) and (6, -12)...
The angle between the normals to the parabola y2 = 24x at the points (6, 12) and (6, -12) is
A
300
B
450
C
600
D
900
Answer
900
Explanation
Solution
Let 2at1 = 12
⇒ t1 = 1
2at2 = -12
t2 = -1
∴ t1t2 = -1 ⇒ (-t1) (-t2) = -1
⇒ (slope of normal at t1)
(slope of normal at t2) = -1
∴ Angle between the normals = 900