27 terms

jilllenzTEACHER

Sine θ

opposite/hypotenuse, y/r

Cosine θ

adjacent/hypotenuse, x/r

Tangent θ

opposite/adjacent, y/x

Cosecant θ

hypotenuse/opposite, r/y

Secant θ

hypotenuse/adjacent, r/x

Cotangent θ

adjacent/opposite, x/y

Coterminal Angles

two angles in standard position that have the same terminal side

Initial Side

the fixed ray of an angle

Period

the least possible value of a for which f(x)=f(x+a)

Reference Angle

the acute angle formed by the terminal side of θ in standard position and the x-axis

Standard Position

the angle positioned so that its vertex is at the origin and its initial side is along the positive x-axis

Terminal Side

a ray of an angle that rotates about the center

Unit Circle

a circle of radius 1 whose center is at the origin of the coordinate system

Cycle

one complete pattern of a periodic function

radian

the measure of an angle θ in standard position whose rays intercept an arc of length 1 unit on the unit circle

Convert Degrees to Radians

The degree of the angle times π/(180°)

Convert Radians to Degrees

The number of radians times 180°/π

Arc Length

s=rθ

angle of depression

The angle between a horizontal line and the line of sight from the observer to an object at a lower level

angle of elevation

The angle between a horizontal line and the line of sight from the observer to an object at a higher level

arcsine

The inverse of y = sine x, written as sin-¹

arccosine

The inverse of y = cosine x, written as cos-¹

arctangent

The inverse of y = tangent x, written as tan-¹

circular function

A function defined using a unit circle.

Law of Cosines

a² = b² + c² -2bcCos A

Law of Sines

sin(A)/a = sin(B)/b = sin(C)/c

quadrantal angle

an angle in standard position whose terminal side coincides with one of the axes.