A. x2+y2=3
B. 9x2+9y2=2
C. 2x2+2y2=9
D. 3x2+3y2=2
The conjugate system of the coaxal system x2+y2+2ax+2by+2λ(ax-by)=0, λ is a parameter, is
The locus of the midpoint of the chord of the circle x2+y2-2x-2y-2=0, which makes an angle of 1200 at the centre is
Let A and B be two fixed points, If a perpendicular p is drawn from A to the polar of B with respect to the circle x2+y2=a2 and perpendicular q is drawn from B to the polar of A then
The circle x2+y2=4 cuts the circle x2+y2-2x-4=0 at the points A and B. If the circle x2+y2-4x-k=0 passes through A and B then the value of k is
The equation of the circle passing through (-7, 1) and having centre at (-4, -3) is
The system of circles orthogonal to x2+y2+2x+4y+7=0 is a member, then the equation of the orthogonal system is
The circle described on the line joining the points (0, 1), (a, b) as diameter cuts the x-axis in points whose abscissa are roots of the equation
If the length of the tangent from (h, k) to the circle x2+y2=16 is twice the length of the tangent from the same point to the circle x2+y2+2x+2y=0, then
The equation of the circle concentric with circlex2+y2-6x+12y+15=0 and of double its area is
The equation of the circle passing through the points of intersection of the circlesx2+y2=5, x2+y2+12x+8y-33=0 and touching x-axis is