A. 1
B. 2
C. 3
D. -1
The number of common tangents to the two circles x2+y2-8x+2y=0 and x2+y2-2x-16y+25=0 is
From any point on the circle x2+y2=a2 tangents are drawn to the circle x2+y2=a2 sin2θ. The angle between them is
If the tangent at P on the circle x2+y2=a2 cuts two parallel tangents of the circle at A and B then PA. PB=
If (1,2), (4, 3) are the limiting points of a coaxal system , then the equation of the circle in its conjugate system having minimum area is
If the lines 2x+3y+1=0, 3x+2y-1=0 intersect the coordinate axes in four concyclic points then the equation of the circle passing through these four points is
If the circles x2+y2=3a2 , x2+y2-6x-8y+9=0 touch externally then a=
The equation to the circles whose radius is 3 and which touches internally the circle x2+y2-4x+6y-12=0 at he point (-1, 1) is
The equation of the chord of contact of the point (4, 2) with respect to the circle x2+y2-5x+4y-3=0 is
The two circles x2+y2=a2, x2+y2=c2(c>0) touch each other if
The area of the quadrilateral formed by the tangents from the point (4,5) to the circle x2+y2-4x-2y-11=0 with a pair of radii joining the points of contact of these tangents is