In the following figure (not to scale), at the centre O if the chord AB subtends double the angle that is subtended by chord CD and the angle $$\angle$$AEB = 2$$\angle$$AOB, then $$\angle$$COD is equal to:
Given, the chord AB subtends double the angle that is subtended by chord CD at the centre O
$$=$$> Â $$\angle$$AOB =Â 2$$\angle$$COD
Let $$\angle$$COD = a
$$=$$> Â $$\angle$$AOB = 2a
$$\angle$$AEB = 2$$\angle$$AOB
$$=$$> Â $$\angle$$AEB = 2(2a) = 4a
In quadrilateral OAEB,
$$\angle$$AOB +Â $$\angle$$OBE +Â $$\angle$$AEB +Â $$\angle$$OAE =Â 360$$^\circ$$
$$=$$>Â 2a +Â 90$$^\circ$$ + 4a +Â 90$$^\circ$$ =Â 360$$^\circ$$
$$=$$>Â 6a +Â 180$$^\circ$$ =Â 360$$^\circ$$
$$=$$>Â 6a =Â 180$$^\circ$$
$$=$$>Â a =Â 30$$^\circ$$
$$=$$> Â $$\angle$$COD =Â 30$$^\circ$$
Hence, the correct answer is Option A
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