OA and OBare the radii of a ciclewith O as centre, <AOB= 1200.Tangents at A and B are drawn to meet at the point C.If OCintersects the circle at the point D, then D divides OCin the ratio ---------------


Given, AOB= 120 degreeWe know that tangent is perpendicular to the radius at point of contact so OAC=OBC=90 degreeSo in quadrilateral OACB, ACB= 360-OAC-OBC-AOB=360-90-90-120=60  degreeNow in triangle OAC and OBC, OA= OB= radius OC = OCAC = BC pair of tangent from external point to circles are equal So OACOBCHence OCA=OCB = 30 degreeNow in right angle triangle AOC, sin 30 = OAOC=rOCOC= 2r CD = OC-OD=2r-r=rSo OD=CD = rHence D divides OCin ratio 1:1 

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