A. 2cosα cosβ cosγ

B. 3cosα cosβ cosγ

C. 4cosα cosβ cosγ

D. 6cosα cosβ cosγ

The equation of the circle passing through the point (1, 2) cutting the circle x^{2}+y^{2}-2x+8y+7=0 orthogonally and bisects the circumference of the circle x^{2}+y^{2}=9 is

Origin is the centre of a circle passing through the vertices of an equilateral triangle whose median is of length 3a, then the equation of the circle is

The circle x^{2}+y^{2}=4x+8y+5=0 intersects the line 3x-4y=m at two distinct points if

The line 2x+3y+19-0and 9x+6y-17=0 cut the coordinate axes in

The midpoint of the chord formed by the polar of (-9, 12) w.r.t x^{2}+y^{2}=100 is