Let be a tangent line to parabola at . If is also a tangent to the ellipse , then the value of is equal to:
- (A)14✓ Correct
- (B)11
- (C)20
- (D)16
Answer: (A)
Solution
The parabola is , and lies on it. Differentiating, , so the slope at is and the tangent is
A line touches exactly when . With and ,
so .
A line touches exactly when . With and ,
so .
JEE Main · 2021 · 17 Mar 2021 · Shift 2 · Single correct option