Pre-Calculus Unit 3 Vocabulary

negative angle

An angle whose generating line is rotated clockwise.

positive angle

An angle whose generating line is rotated counterclockwise.

secant

In a right triangle, the ratio of the hypotenuse compared to the side adjacent∠ θ

cosecant

In a right triangle, the ratio of the hypotenuse compared to the side opposite angle theta, ∠θ

cosine

In a right triangle, the ratio of the side adjacent ∠θ, compared to the hypotenuse

cotangent

In a right triangle, the ratio of the side adjacent ∠θ, compared to the side opposite∠θ

sine

In a right triangle, the ratio of the side opposite ∠θ, compared to the hypotenuse

tangent

In a right triangle, the ratio of the side opposite ∠θ, compared to the side adjacent∠θ

standard position

The position of an angle when the vertex is at the origin and the initial side of the angle coincides with the positive part of the x-axis.

unit circle

a circle with a radius = 1

equilateral triangle

a triangle composed of angles that all equal 60 degrees

Isosceles right triangle

a triangle with one right angle and two equal 45 degree angles

radian

a unit of angular measure equal to the acute angle at the center of a circle formed by two radii whose endpoints define an arc equal to the length of the radius of the circle

central angle

an angle that has the measure of one radian if it intercepts an arc of length equal to the radial length

right angle

an angle that measures 90 degrees

acute angle

an angle that measures 90 degrees or less

obtuse angle

an angle that measures 90 degrees or more

special angles

angles with measures of 30, 45, and 60, degree angles and their multiples

quadrantal angles

any angle whose measure is a multiple of 90, 180 or 270 degrees