hey boyz n gals it is imp. topic in entrance exams so i want to throw light on this topic i hope it will benefit u

RADICAL AXIS

The radical axis of two circle axis is locus of point , which moves so that the lenghts of tangents drawn from it to the two circles r equal
if S1 be equation of one cirle and S2 be equation of another circle than S1-S2=0
is equation of common chord however same becomes equation of common tangent if circle touches each other

RADICAL CENTRE

let S1=0, S2=0 ,S3=0 be three circles then their radical axis taken in pairs r parallel or concurrent .if they r not parallel their points of concurrency is called radical centre of circles


RADICAL CIRCLE

let a (S.,K) be radical centre and l be length of tangents from radical centres A,then the circle (x-S)^2 (y-K)^2=l^2 is called radical circle

hey guyzzzzz this article is EXCLUSIVELY dedicated to my 100th !!!!!!! post

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