Calculate sin75°sin15° =

Question: Calculate sin75°sin15° =Solution:sin75°sin15°= sin(90°-15°).sin15°= cos15°sin15°= (1/2) × 2cos15°sin15°= (1/2) × sin(2 × 15°)= (1/2) × sin30°= (1/2) × (1/2)= 1/4