sin 75° equals:
A(√6 + √2)/4
B(√6 − √2)/4
C(√3 + 1)/4
D1/2
Answer & Solution
Correct answer: A. (√6 + √2)/4
1. 75° = 45° + 30°.
2. sin 75° = sin 45° cos 30° + cos 45° sin 30° = (√2/2)(√3/2) + (√2/2)(1/2) = (√6 + √2)/4.
3. Distractor (B) is sin 15° (= cos 75°).
_Source: NCERT Class 11 Maths Ch 3 §3.4 Sum Formulas_
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