Theorem: y and x are given in a different variable that is θ . We can find by finding and and then dividing them to get the required thing.

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= 2cosθ – 2cos2θ ………..(1)

= -2sinθ + 2sin2θ ……….(2)

Dividing (1) and (2), we get

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By factorising numerator, we get

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Foe simplicity let’s take θ/2 as x.

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