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A geometry problem by Abhay Kumar

Geometry Level 2

If \( \cos \theta - \sin \theta = \sqrt2 \sin \theta \), which of the following is equal to \( \cos \theta + \sin \theta\)?

\[ \sqrt2 \cot\theta \] \[ \sqrt2 \cos\theta \] \[ \sqrt2 \tan\theta \] \[ \sqrt2 \csc\theta \]

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by Abhay Kumar

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