Learn how to use the unit circle to define sine, cosine, and tangent for all real numbers.

Trigonometry Course: Trigonometry > Unit 2 Lesson 1: Unit circle introduction Unit circle Unit circle The trig functions & right triangle trig ratios

Sal finds several trigonometric identities for tangent by considering horizontal and vertical symmetries of the unit circle.

Trigonometry 4 units · 36 skills Unit 1 Right triangles & trigonometry Unit 2 Trigonometric functions Unit 3 Non-right triangles & trigonometry Unit 4 Trigonometric equations and identities Course challenge

For each point on the unit circle, select the angle that corresponds to it. Click each dot on the image to select an answer.

What is the unit circle? The unit circle is a circle with a radius of 1 centered at the origin. We can use the unit circle to help define the trigonometric functions and visualize their values. Learn more with our …

Unit circle trigonometry | Lesson Angles, arc lengths, and trig functions — Basic example Angles, arc lengths, and trig functions — Harder example Unit circle trigonometry: foundations

If you have a point (x, y), the distance from the origin to (x, y) is given by √ (x²+y²). The unit circle is the set of points where this distance is 1, where √ (x²+y²)=1. Squaring both sides of the equation, this is …

High school geometry 9 units · 90 skills Unit 1 Performing transformations Unit 2 Transformation properties and proofs Unit 3 Congruence Unit 4 Similarity Unit 5 Right triangles & trigonometry Unit 6 …

Sal finds the trigonometric values of π/4 using the unit-circle definition. Created by Sal Khan.