MAS Tutoring - Trigonometry.

\sin θ = \frac{opposite}{hypotenuse}

\cos θ = \frac{adjacent}{hypotenuse}

\tan θ = \frac{opposite}{adjacent}

Some say "S^OH C^AH T^OA"

Trig Values to Remember

Angle	degrees / °	0	30	45	60	90
Angle	radians	0	$\frac{π}{6}$	$\frac{π}{4}$	$\frac{π}{3}$	$\frac{π}{2}$
sine		0	$\frac{1}{2}$	$\frac{\sqrt{2}}{2}$	$\frac{\sqrt{3}}{2}$	1
cosine		1	$\frac{\sqrt{3}}{2}$	$\frac{\sqrt{2}}{2}$	$\frac{1}{2}$	0
tangent		0	$\frac{\sqrt{3}}{3}$	1	$\sqrt{3}$	[undefined]

\frac{\sin A}{a} = \frac{\sin B}{b} = \frac{\sin C}{c}

c^{2} = a^{2} + b^{2} - 2 a b \cos C

tan x = \frac{sin x}{cos x}

cosec x = \frac{1}{sin x}

sec x = \frac{1}{cos x}

cot x = \frac{1}{tan x}

\sin^{2} θ + \cos^{2} θ = 1

1 + {cot}^{2} θ = {cosec}^{2} θ

\tan^{2} θ + 1 = \sec^{2} θ

\sin (A \pm B) = \sin A \cos B \pm \sin B \cos A

\sin 2 A = 2 \sin A \cos A

\cos (A \pm B) = \cos A \cos B \mp \sin B \sin A

\cos 2 A = \cos^{2} A - \sin^{2} A

= 2 \cos^{2} A - 1

= 1 - 2 \sin^{2} A

\tan (A \pm B) = \frac{\tan A \pm \tan B}{1 \mp \tan A \tan B}

\tan 2 A = \frac{2 \tan A}{1 - \tan^{2} A}