Question
If the chord of contact of tangents from a point on the circle $x^{2}+y^{2}=a^{2}$ to the circle $x^{2}+y^{2}=b^{2}$ touches the circle $x^{2}+y^{2}=c^{2}$, then $a, b, c$ are in(A) A. $P$.(B) G. P.(C) H. P.(D) none of these
Step 1
Since it lies on the circle, we have $x_1^{2}+y_1^{2}=a^{2}$. Show more…
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If the locus of a point which moves so that the line joining the points of contact of the tangents drawn from it to the circle $x^{2}+y^{2}=b^{2}$ touches the circle $x^{2}+$ $y^{2}=a^{2}$, is the circle $x^{2}+y^{2}=c^{2}$, then $a, b, c$ are in (A) A. P. (B) G. P. (C) H. P. (D) none of these
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