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Question
The value of sin 15° is:
Options
`(sqrt3 + 1)/(2sqrt2)`
`(sqrt3 - 1)/(2sqrt2)`
`sqrt3/sqrt2`
`(sqrt3)/(2sqrt2)`
Solution
`(sqrt3 - 1)/(2sqrt2)`
Explanation:
sin 15° = sin(45° – 30°)
= sin 45° cos 30° – cos 45° sin 30°
`= 1/sqrt2 xx sqrt3/2 - 1/sqrt2 xx 1/2`
`=(sqrt3 - 1)/(2sqrt2)`
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