Trigonometric Functions and Identities
The six ratios that connect the angles and sides of a right triangle, and the equations that always hold true.
The Six Trigonometric Functions
$\sin\theta$, $\cos\theta$, $\tan\theta$, $\csc\theta$, $\sec\theta$, and $\cot\theta$.
Fundamental Identity
$$\sin^2\theta + \cos^2\theta = 1$$Addition Formulas
$$\sin(A+B) = \sin A \cos B + \cos A \sin B$$$$\cos(A+B) = \cos A \cos B - \sin A \sin B$$Lesson 6 of 27