The sine of an angle θ is the ratio of the length of the side opposite to θ in a right triangle to the length of the hypotenuse.
Cosine (cosθ): The cosine of an angle θ is the ratio of the length of the adjacent side to θ in a right triangle to the length of the hypotenuse.
Tangent (tanθ): The tangent of an angle θ is equal to sine divided by cosine, or opposite over adjacent.
Cosecant (cscθ): The cosecant function is equal to 1 divided by sine, or hypotenuse over opposite.