Pre-calculus Identification Sigma Reviewer

This is the great Greek astronomer and mathematician who already knew then that the earth is a sphere, and used angle measures to determine the radius of the earth

Hipparchus

This is the union of two rays with a common endpoint called the vertex

Angle

It is formed by rotating a ray through its endpoint called the vertex

Angle

What is the starting position of the ray of the angle?

Initial side

The ending position of the angle

Terminal side

In trigonometry, this is the amount of an angle's rotation

Measure of an angle

In what way does a counterclockwise angle rotate?

Positive

In what way does a clockwise angle rotate?

Negative

What are the ways an angle can be labeled:

1. Capital letters of the English alphabet

2. Small letters of the Greek Alphabet

In a coordinate system, an angle is said to be in what position of its initial side lies along the positive x-axis and its vertex at the origin

Standard position

0°<90° or -360°< -270°

Quadrant I

90°<180° or -270°< -180°

Quadrant II

180°<270° or -180°< -90°

Quadrant III

270°<360° or -90°<0°

Quadrant IV

Angles that do not lie in quadrants but on the axes are called?

Quadrantal angles

If the angles have the same terminal sides, they are?

Coterminal

This part of a circle is the region bounded by 2 radii and an arc intercepted by a central angle

Sector

A circle whose center is at the origin (0, 0) and with a radius of 1 unit

Unit Circle

Are defined in terms of the coordinates of trigonometric points on the unit circle

Circular Functions

An equation that is true for all value/s of the variable/s for which both sides are defined

Identity

An equation that is only true for some value/s of the variable/s

Conditional Equation