Evaluate the following: sin 36° cos 9° + cos 36° sin 9° - Mathematics

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Evaluate the following:
sin 36° cos 9° + cos 36° sin 9°

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उत्तर

$\sin 36^{\circ} \cos 9^{\circ} + \cos 36^{\circ} \sin 9^{\circ}$
$= \sin (36^{\circ} + 9^{\circ}) [Using \sin A \cos B + \cos A \sin B = \sin (A + B)]$
$= \sin 45^{\circ} = \frac{1}{\sqrt{2}}$

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Trigonometric Functions of Sum and Difference of Two Angles

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Q 7.3 Q 7.2 Q 7.4

पाठ 7: Values of Trigonometric function at sum or difference of angles - Exercise 7.1 [पृष्ठ १९]

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पाठ 7 Values of Trigonometric function at sum or difference of angles
Exercise 7.1 | Q 7.3 | पृष्ठ १९

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Trigonometric Functions of Sum and Difference of Two Angles

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Evaluate the following: sin 36° cos 9° + cos 36° sin 9° - Mathematics

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Evaluate the following: sin 36° cos 9° + cos 36° sin 9° - Mathematics

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