A. 4
B. 5
C. 3
D. none
The lengths of the chords of the circle x2+y2-2x-6y-15=0 which make an angle of 600 at (1, 3) and the locus of the midpoints of all such chords are
The shortest distance from (-2, 14) to the circles x2+y2-6x-4y-12=0 is
If the distances from the origin to the centres of three circles x2+y2-2k, x=c2 (i=1,2,3),are in G.P, then the lengths of the tangents drawn to them from any point on the circle x2 + v2 = c2 are in
If α, β are the roots of x2+ ax+b=0 and γ, δ are the roots y2+cx+d=0 then the equation of the circle having the line joining (α, γ), (β, δ) as diameter is
The least distance of the line 8x-4y+73=0 from the circle 16x2+16y2+48x-8y-43=0 is
The equation of the circle with centre (-1, 1) and touching the circle x2+y2-4x+6y-3=0 externally is
The orthocentre of triangle formed by the lines x + 3y = 10 and 6x<sup>2</sup> + xy - y<sup>2</sup> = 0 is:
B and C are two points on the circle x2+y2=a2. From a point A(b, c) on that circle AB=AC=d. The equation to Bc is
The locus of the centre of the circles which touché both the circles x2+y2=a2 and x2+y2=4ax externally has the equation
The equation of the circle belonging to the coaxal system of which (1, 2)(4, 3) are the limiting points and passing through the origin is