मराठी

Find the value of: sin 75°

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प्रश्न

Find the value of: sin 75°

बेरीज
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उत्तर

sin (75°) = sin (45° + 30°)

= sin 45° cos 30° + cos 45° sin 30°

[∵ sin (A + B) = sin A cos B + cos A sin B]

= `(1/sqrt2) (sqrt3/2)+ (1/sqrt2), (1/2)`

[∵ sin 45° = `1/sqrt2,cos 30°= sqrt3/2, sin 30° = 1/2`]

= `(sqrt3+1)/(2sqrt2)`

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पाठ 3: Trigonometric Functions - EXERCISE 3.3 [पृष्ठ ६७]

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एनसीईआरटी Mathematics [English] Class 11
पाठ 3 Trigonometric Functions
EXERCISE 3.3 | Q 5. (i) | पृष्ठ ६७

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