PAB is a secant to a circle intersecting the circle at A and B . PT is a tangent, prove that PA x PB = PT². Using the above prove the following: ABC is an isosceles triangle, such that AB=AC and the point D is the midpoint of AC . A circle is drawn taking BD as diameter, which intersects AB at E .Prove that AE = 1/4AC.
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Now using the above result
AE × AB = AD2