Question #8e1d5

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Answer 1 · 2016-07-27T12:52:01

#sqrt((1/2)(1-((sqrt 3 + 1)/(2 sqrt 2))))#

#=0.1305#, nearly

Angle is in degree unit.

#sin(15/2)#

#=sqrt((1-cos 15)/2)#

#=sqrt((1/2)(1-cos(45-30))#

#=sqrt((1/2)(1-(cos 45 cos 30+sin 45 sin 30))#

#=sqrt((1/2)(1-((1/sqrt 2)(sqrt 3/2)+(1/sqrt 2)(1/2)))#

#=sqrt((1/2)(1-((sqrt 3 + 1)/(2 sqrt 2))))#

#0.1305#, nearly