let the point be dcos
,dsin
chord of contact is T=0
=xdcos/a2-ydsin/b2 - 1 =0
chord whose midpoint is h,k is T=S1
=xh/a2+yk/b2=h2/a2+y2/b2
the coeff of x,y and the const term would be proportional
.: dcos/h=dsin/k=1/h2/a2+y2/b2
=>sin=k/root(h2+k2)
dsin/k (h2/a2+y2/b2) = 1
.:d2(h2/a2+y2/b2)2=h2+k2
so locus is
Moderation Team
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