A circle of radius r touches the parabola `x^2+4ay=0 (a>0)` at the vertex of the parabola. The centre of the circle lies below the vertex and the circle lies entirely within the parabola. Then the largest possible value of r is

A circle of radius r, rne0 touches the parabola y^(2)+12x=0 at the vertex of the parabola. The centre of the circle lies to the left of the vertex and the circle lies entirely witin the parabola. Then the interval(s) in which r lies can be

A circle of radius r,r ne 0 touches the parabola y ^(2) + 12 x =0 at the ertex of the parabola. The centre of the circle lies to the left of the vertex and the circle lies entriely within the parabola. Then the intervals in which, r lies can be

The vertex of the parabola y^2 + 4x = 0 is

A circle of radius 4 drawn on a chord of the parabola y^(2)=8x as diameter touches the axis of the parabola. Then the slope of the chord is

A circle of radius 4 drawn on a chord of the parabola y^(2)=8x as diameter touches the axis of the parabola. Then the slope of the chord is

A circle of radius r drawn on a chord of the parabola y^(2)=4ax as diameter touches theaxis of the parabola.Prove that the slope of the chord is (2a)/(r)

The vertex of the parabola y^2 = 8x is at the centre of a circle and the parabola cuts the circle at the ends of itslatus rectum. Then the equation of the circle is