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Question
Find the value of sin 105°
Solution
sin 105° = sin(90° + 15°)
= cos 15°
= cos(45° – 30°)
= cos 45° cos 30° + sin 45° sin 30°
= `1/sqrt(2)*sqrt(3)/2 + 1/sqrt(2)*1/2`
sin(105°) = `1/(2sqrt(2)) (sqrt(3) + 1)`
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