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    The chord of contact of tangents drawn from a point on the circle x² + y² = a² to the circle x² + y² = b² touches the circle x² + y² = c² such thatb
    Question

    The chord of contact of tangents drawn from a point on the circle x² + y² = a² to the circle x² +
    y² = b² touches the circle x² + y² = c² such thatbm=ancp, b^m=a^n c^p,​ where m, n, p, ∈ N. Find the value of
    m + n + p + 10.

    A.

    18

    B.

    10

    C.

    14

    D.

    12

    Correct option is C

    Given:

    The chord of contact of tangents drawn from a point on the circle x² + y² = a²

    to the circle x² +y² = b² touches the circle x² + y² = c²

    such that bm=ancpb^m=a^n c^p, where m, n, p, ∈ N. 

    m + n + p + 10. 

    Solution:

    Let there is a point P(h, k) on the circlex2+y2=a2. x^2 + y^2 = a^2.​​

    (h, k) will satisfy the equationx2+y2=a2 x^2 + y^2 = a^2​.

    =>h2+k2=a2 h^2 + k^2 = a^2

    ​​

    The equation of the chord of the contact of tangents drawn from the point P(h, k) to the circlex2+y2=b2 x^2 + y^2 = b^2​ will be

    hx+ky=b2hx + ky = b^2​​

    The perpendicular distance of this tangent from the center of the circle x2+y2=c2 x^2 + y^2 = c^2 will be equal to the radius of the circle.

    b2h2+k2=c\left| \frac{-b^2}{\sqrt{h^2 + k^2}} \right| = c 

    b2a=c\left| \frac{-b^2}{a} \right| = c 

    b2=acb^2 = ac​​

    Comparing it with bm=ancpb^m=a^n c^p​​

    => p = 1, m =2 ,n = 1 

    so, ​m + n + p + 10.  =  10+1+1=+2   

                                             =14


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