If the locus of the mid points of the chords of the circle x2+y2=16 which are
tangents to the hyperbola 9x2-16y2=144 is given by (x2+y2)a= bx2-cy2 then
find the value of a+b+c.
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2 Answers
mohit sengar
·2010-09-11 06:15:37
let the mid point of chord to the circle be (p,q)
then T=S1
so, px+qy = p2 + q2
it can also be written as y = -px/q + p2/q + q2/q
acc to the conditon of tangency , we have
c2 = a2m2 - b2
( p2/q + q2/q)2 = 16p2/q2 - 9
on solving it u get a+ b+ c = 27