Explain thales theorem?

1 Answer
May 3, 2017

Please see below.

Explanation:

Thales theorem states that the diameter of a circle always subtends a right angle on any point on the circle. For example see the following figure.

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Here when ends of diameter are joined to any point on the circumference, they all subtend a right angle.

Thales theorem is a corollary of the theorem, which states that the angle subtended by an arc at any point on the circumference is half of the angle subtended by it at the centre.

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For example if the arc #AC# subtends angle #/_AOC# at the centre and #/_ABC# any where else on the circumference,

#/_ABC=1/2/_AOC#

and if #AOC# is a diameter, it forms an angle of #180^@# and angle subtended by it at any point on circumference is#1/2xx180^@=90^@#