One or more options correct
From the point , two tangents are drawn to the parabola , touching it at and . Which of the following is (are) correct?
- A. The chord of contact is
- B. The area of triangle is
- C. The circumcircle of triangle passes through the focus
- D. The tangents and are perpendicular to each other
Show answer and solution
Answer: A, B
The tangent at is . It passes through if , so and the contact points are , . (A) The chord of contact is -polar: , i.e. ; it contains both and ; correct. (B) Area (also ); correct. (C) The circumcircle of is , which at gives ; the focus property belongs to the triangle formed by three tangents, not to the triangle with the contact points; incorrect. (D) The slopes are and , product (the angle is ); incorrect. Answer: A and B.
Saved on this device. Sign in or create a free account to keep it on every device.