1+2sinβcosβ cos²β+sin²β+2sinβcosβ (cosβ+sinβ)²
____________ = _____________________ = ___________ = 1
(cosβ+sinβ)² (cosβ+sinβ)² (cosβ+sinβ)²
sin⁴β- cos⁴β (sin²β-cos²β)(sin²β+cos²β)) -(cos²β-sin²β)(sin²β+cos²β)
___________ = ______________________ = ______________________ =
(cos²β-sin²β) cos²β-sin²β) (cos²β-sin²β)
= -(sin²β+cos²β) =-1