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प्रश्न
The value of \[\tan x \sin \left( \frac{\pi}{2} + x \right) \cos \left( \frac{\pi}{2} - x \right)\]
विकल्प
1
-1
- \[\frac{1}{2} \sin 2x\]
none of these.
उत्तर
none of these.
\[\text{ We have } , \]
\[tan\theta \sin\left( \frac{\pi}{2} + x \right) \cos\left( \frac{\pi}{2} - x \right)\]
\[ = \frac{\text{ sin } x}{\text{ cos } x}\text { cos } x \text{ sin } x\]
\[ = \sin^2 x\]
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