alleryFind sin(15°):
A1/√2
B(√3 + 1)/(2√2)
C1/4
D(√3 - 1)/(2√2)
Answer & Solution
Correct answer: D. (√3 - 1)/(2√2)
We have sin(15°) = sin(45° - 30°).
Then sin(15°) = sin45 cos30 - cos45.
Then sin30 = (1/√2)(√3/2) - (1/√2)(1/2).
So sin30 = (√3 - 1)/(2√2).
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