KVPY2011MathematicsParabola
In the x y -plane, three distinct lines l₁, l₂, l₃ concur at a point ( , 0) . Further the lines l₁, l₂, l₃ are normals to the parabola y²=6 x at the points A= (x₁, y₁ ), B= (x₂, y₂ ), C= (x₃, y₃ ) respectively. Then we have -
Options
- A< -5
- B>3
- C-5 < < -3
- D0 < < 3
Correct answer
B. >3
Step-by-step solution
Any normal y = mx -2 am - am ³ Here a =3 / 2 through ( , 0) array l 0= m -2 am - am ³ ~m =0, =2 a + am ² ~m ²= a -2>0 >2 a >3 array