8 cos 82,5 sin 37,5 = ..........

= 8/2 (sin (82,5 + 37,5) - sin (82,5 - 37,5) )
= 4 (sin 120 - sin 45)
= 4 (1/2√3 - 1/2√2)
= 4 (1/2 (√3-√2) )
= 2 (√3-√2)

= 4 (sin (82,5 + 37,5) - sin (82,5 - 37,5) )
= 4 (sin 120 - sin 45)
= 4 (1/2√3 - 1/2√2)
= 2 ( √3-√2 )
= 2√3- 2√2)