Cos^2 15° - cos^2 75°=√3/2
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Answer:
cos² 15° - cos²75° = √3/2
Step-by-step explanation:
LHS = cos² 15° - cos²75°
= cos² 15° - cos²(90°-15°)
= cos² 15° - sin² 15
= cos²(2×15°)
/* cos²A - sin²A = cos2A*/
= cos30°
= √3/2
= RHS
Therefore,.
cos² 15° - cos²75° = √3/2
•••♪
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