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3.    Evaluate :  

   (ii)\sin 25^{o}\cos 65^{o}+\cos 25^{o}\sin 65^{o}

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\sin 25^{o}\cos 65^{o}+\cos 25^{o}\sin 65^{o}

We know that 
\\\sin(90^0-\theta) = \cos \theta \\\cos (90^0-\theta) = \sin \theta

Therefore,

\\\sin 25^{o}\cos (90^0-25^{o})+\cos 25^{o}\sin (90^0-25^{o})\\ \sin 25^0.\sin 25^0 + \cos 25^0.\cos 25^0\\ sin^2 25^0+\cos ^225^0\\ 1

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manish

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