Sin 10° * sin 50° * sin 70° = ?

Sin (10°) sin (50°) sin (70°) = 1/2 (cos (-40°) - cos (60°)) sin (70°) = (sin (70°)) / 2 * (2cos (40°) - 1) / 2 = (2sin (70°) cos (40°) - sin (70°)) / 4 = ((sin (110°) + 1/2) - sin (70°)) / 4 = (cos (20°) + 1/2-sin (70°)) / 4 = (sin (70°) + 1/2-sin (70°)) / 4=1/8=0,125