Sqrt ( 1- cost)
Sqrt ( 1 - cos^2t) / Sqrt (1 + Cost)
Sqrt ( Sin^2t) / Sqrt (1 + Cost)
Sint / Sqrt (1 + Cost)
Integral becomes: I = Int ( sint/ sqrt( 1+ Cost) ) dt
Let u = 1 + Cost
du/dt= -Sint
du = -Sintdt
Integral becomes: I = -Int ( -du/Sqrt (u) )
I = -2 Sqrt(u) + C
I = -2 Sqrt (1 + Cost) + C