Question
Question: If y<sub>1</sub>, y<sub>2</sub> are the ordinates of two points P and Q on the parabola and y<sub>3<...
If y1, y2 are the ordinates of two points P and Q on the parabola and y3 is the ordinate of the point of intersection of tangents at P and Q, then
A
y1, y2, y3 are in A.P.
B
y1, y3, y2 are in A.P.
C
y1, y2, y3 are in G.P.
D
y1, y3, y2 are in G.P.
Answer
y1, y3, y2 are in A.P.
Explanation
Solution
P(x1, y1) Q(x2, y2)
Point of intersection of P and Q.
(x3, y3) = (x1x2,2y1+y2)
\ y3 = 2y1+y2̃ y1, y3, y2 are in A.P.