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प्रश्न
Find the value of:
sin 15°
उत्तर
sin 15°
= sin (45° – 30°)
= sin 45° cos 30° – cos 45° sin 30°
= `(1/sqrt(2))(sqrt(3)/2) - (1/sqrt(2))(1/2)`
= `(sqrt(3) - 1)/(2sqrt(2)`
Notes
Answer given in the textbook is `(sqrt(3) + 1)/(2sqrt(2)`. However, as per our calculation it is `(sqrt(3) - 1)/(2sqrt(2)`.
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