The equation of four circles are `(x+-a)^2+(y+-a2=a^2` . The radius of a circle touching all the four circles is `(sqrt(2)+2)a` (b) `2sqrt(2)a` `(sqrt(2)+1)a` (d) `(2+sqrt(2))a`

Consider four circles (x+-1)^2+(y+-1)^2=1 . Find the equation of the smaller circle touching these four circles.

The equation of a circle is x^2+y^2=4. Find the center of the smallest circle touching the circle and the line x+y=5sqrt(2)

The equation of a circle is x^2+y^2=4. Find the center of the smallest circle touching the circle and the line x+y=5sqrt(2)

Three equal circles each of radius r touch one another. The radius of the circle touching all the three given circles internally is (2+sqrt(3))r (b) ((2+sqrt(3)))/(sqrt(3))r ((2-sqrt(3)))/(sqrt(3))r (d) (2-sqrt(3))r

The radius of the circle touching the straight lines x-2y-1=0 and 3x-6y+7=0 is (A) 1/sqrt(2) (B) sqrt(5)/3 (C) sqrt(3) (D) sqrt(5)

Find the equation of the circle with: Centre (a , a) and radius sqrt(2)a .

The radius of the circle passing through the points (1, 2), (5, 2) and (5, -2) is : (A) 5sqrt(2) (B) 2sqrt(5) (C) 3sqrt(2) (D) 2sqrt(2)

The line 2x-y+1=0 is tangent to the circle at the point (2, 5) and the center of the circle lies on x-2y=4. The radius of the circle is (a) 3sqrt(5) (b) 5sqrt(3) (c) 2sqrt(5) (d) 5sqrt(2)

Find the equation of the circle with centre : (1, 1) and radius sqrt(2)

A circle S of radius ' a ' is the director circle of another circle S_1,S_1 is the director circle of circle S_2 and so on. If the sum of the radii of all these circle is 2, then the value of ' a ' is (a) 2+sqrt(2) (b) 2-1/(sqrt(2)) (c) 2-sqrt(2) (d) 2+1/(sqrt(2))