# Unit5Vocabulary Flashcards

Inverse Cosine

The inverse of the cosine function that will take a trigonometric ratio as input and produce the angle associated with that ratio. Denoted with a -1 superscript:

cos^{-1}(x)

Angle of Depression

The angular measurement between the horizontal axis down to an object.

Pi

The angular distance between the positive x axis and the negative x axis in radians. Denoted by the Greek letter π it is an irrational number starting with the value 3.1415926…

Inverse Tangent

The inverse of the tangent function that will take a trigonometric ratio as input and produce the angle associated with that ratio. Denoted with a -1 superscript:

tan^{-1}(x)

Sine

Sine of an angle is defined as the ratio of the opposite side over the hypotenuse.

** Soh** Cah Toa

Side-Side-Angle

This is the case where you have the values of 2 sides and an angle in sequence as you rotate around a triangle in either the clockwise or counter-clockwise direction. This triangle can be solved with the Law of Sines but is known as the Ambiguous case since two possible triangles exist with the same 2 sides and angle.

Cosine

Cosine of an angle is defined as the ratio of the adjacent side over the hypotenuse.

Soh ** Cah** Toa

Law of Cosine

Quotient Identities

Radian

The angular distance of a sector of a circle where the arc length of the sector is equal to the length of the radius.

Tangent

Tangent of an angle is defined as the ratio of the opposite side over the adjacent side.

Soh Cah __Toa__

Terminal Side

Obtuse Triangle

A triangle that has one angle greater than 90°.

Side-Side-Side

This is when you have the value of all 3 sides of a triangle. This triangle can be solved using the Law of Cosines.

Phase Shift

The horizontal translation of a trigonometric function.

Arc Length

Cosecant

Represented by the letters csc it is an inverse identity as defined below:

Asymptote

A value of the domain for which a function is undefined or for which the range of a function will never exceed. On a graph it is noted as a dotted line which the function’s graph never touches.

Negative Angle Identities