JEE Advanced2006MathematicsParabolaActual
Paragraph: Read the following passage and answer the questions. Let A B C D be a square of side length 2 units. C₂ is the circle through vertices A, B, C, D and C₁ is the circle touching all the sides of square A B C D . L is the line through A . Question: A circle touches the line L and the circle C₁ externally such that both the circles are on the same side of the line, then the locus of centre of the circle is
Options
- Aellipse
- Bhyperbola
- Cparabola
- Dparts of straight line
Correct answer
C. parabola
Step-by-step solution
Let C be the centre of the required circle. Now, draw a line parallel to L at a distance of r₁ (radius of C₁ ) from it. Now, C P₁=A C C lies on a parabola.