Question

Tangents are drawn from any point on the circle $x ^ { 2 } + y ^ { 2 } = a ^ { 2 }$ to the circle $x ^ { 2 } + y ^ { 2 } = b ^ { 2 }$. If the chord of contact touches the circle then

• A. a, b, c are in A.P
• B. a, b, c are in G.P.
• C. a, b, c are in H.P
• D. a, c, b are in G.P.

Answer 1

Answer: (B)

a, b, c are in G.P.

Answer 2

Chord of contact of any point $x ^ { 2 } + y ^ { 2 } = c ^ { 2 }$

Hence, Radius = Perpendicular distance of chord from centre.

.

Hence a,b,c are in G.P