When 3 π

When 3 π

Solution from radical (1 + cosx / 2) - radical (1-cosx / 2)
=√(1+cosx/2)-√(1-cosx/2)
=√(1+(2cos²x/2-1)/2)-√(1-(1-2sin²x/2)/2)
=√cos²x/2-√sin²x/2
From 3 π