Search results:
71.
Half Angle Formula of Sine
$\sin \dfrac{\alpha}{2} = \pm \sqrt{\dfrac{1-\cos\alpha}{2}}$
72.
Half Angle Formula of Cosine
$\cos \dfrac{\alpha}{2} = \pm \sqrt{\dfrac{1+\cos\alpha}{2}}$
73.
Half Angle Formula of Tangent
$\tan\dfrac{\alpha}{2} = \pm \sqrt{\dfrac{1-\cos\alpha}{1+\cos\alpha}}$
74.
Half Angle Formula of Tangent
$\tan \dfrac{\alpha}{2} = \dfrac{\sin\alpha}{1+\cos\alpha}$
75.
Half Angle Formula of Tangent
$\tan\dfrac{\alpha}{2} = \dfrac{1-\cos\alpha}{\sin\alpha}$
76.
Half Angle Formula of Cotangent
$\cot \dfrac{\alpha}{2} = \pm \sqrt{\dfrac{1+\cos\alpha}{1-\cos\alpha}}$
77.
Half Angle Formula of Cotangent
$\cot\dfrac{\alpha}{2} = \dfrac{\sin\alpha}{1-\cos\alpha}$
78.
Half Angle Formula of Cotangent
$\cot \dfrac{\alpha}{2} = \dfrac{1+\cos\alpha}{\sin\alpha}$