" (i) concentric circles with centre at "(1,2)

Find the differential equation of system of cocentric circles with centre (1,2)

Find the differential equation of system of cocentric circles with centre (1,2)

Two concentric circles have centres at (1,2) and radii r and 2r. The circle x^(2)+y^(2)+2x-7y-2=0 cuts these circles such that the common chord with one of the circles is a tangent to the other.Find the equation of both the circles.

Let S and S' be two (non - concentric circles with centres Aand B and radii r_(1),r_(2)and d be the distance between their centres , then one circle lies completely inside the other circle iff

Order of the differential equation of the family of all concentric circles centred at (h,k) is