Cosec(65+θ)−sec(25−θ)−tan(55−θ)+cot(35+θ)
=sec[90−(65+θ)]−sec(25−θ)−cot[90−(55−θ)]+cot(35+θ)
sincesec(90−x)=cosecx,cot(90−x)=tanx
=sec(25−θ)−sec(25−θ)−cot(35+θ)+cot(35+θ)
=0