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Ca and CB are tangent lines of circle O, and the tangent points are a and B respectively. They connect the intersection chord ab of OC to point D. It is known that the radius of circle O is 4 and the chord AB = 4. To prove that OC bisects AB 2 vertically: to find out The length of AC
It is proved that connecting OA, ob ∵ Ca and CB is tangent ∵ Cao = ≌ CBO = 90 & # 186; CA = CB ∵ co = Co ≌ RT ≌ Cao ≌ RT ≌ CBO (HL) ∵ ACO = ∩ BCO ∩ OC vertical bisection AB [isosceles triangle three lines in one, vertex bisection line is also vertical line] 2.
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