If `d_1,d_2` (d_2>d_1) be the diameters of two concentric circles and c be the length of a chord of a circle which is tangent to the other circle prove that `d_2^2=c^2+d_1^2`

If d_(1),d_(2)(d_(2)2>d 1) be the diameters of two concentric circles and c be the length of a chord of a circle which is tangent to the other circle prove that d_(2)^(2)=c^(2)+d_(1)^(2)

If radii of the two concentric circles are 15cm and 17cm, then the length of each chord of one circle which is tangent to other is: 8cm(b)16cm(c)30cm(d)17cm

If D is thedaneter of the brger circle and d the diameter of the small circle then D+d=?

In the following diagram four circles are tangent to every other circle. The radius of each of the circles A,B and C is 1. Find the radius of circle D, which is tangent to all the three given circles and lies at the centre.

The radii of two concentric circle are 13 cm and 8 cm. AB is a diameter of the bigger circle and BD is a tangent to the smaller circle touching it at D and the bigger circle at E. Point A is joined to D. Find the length of AD.

If the circumference and the area of a circle are numerically equal, then diameter of the circle is (a) pi/2 (b) 2pi (c) 2 (d) 4

A line meets the coordinate axes at A and B . A circle is circumscribed about the triangle O A Bdot If d_1a n dd_2 are distances of the tangents to the circle at the origin O from the points Aa n dB , respectively, then the diameter of the circle is (2d_1+d_2)/2 (b) (d_1+2d_2)/2 d_1+d_2 (d) (d_1d_2)/(d_1+d_2)

If the length of the chord of the circle x^2+y^2=4 through (1,1/2) which is of minimum length is d, find d^2 .