Interactive Unit Circle Explorer

Understand trigonometric functions visually. Explore how angles relate to coordinates, and master sine, cosine, and tangent through hands-on interaction.

Try It Yourself!

Play with the interactive Unit Circle below. See how different angles (in radians or degrees) affect sine, cosine and tangent. Hover over the circle to explore values - the line will automatically follow your mouse!

Cosine
cos = 0.7071
x-coordinate
Sine
sin = 0.7071
y-coordinate
Tangent
tan = 1.0000
sin/cos

🧮 Quick Calculator

📊 Common Angles

DegreesRadianscos(θ)sin(θ)tan(θ)
0°0100
30°π/6√3/21/2√3/3
45°π/4√2/2√2/21
60°π/31/2√3/2√3
90°π/201
120°2π/3-1/2√3/2-√3
135°3π/4-√2/2√2/2-1
150°5π/6-√3/21/2-√3/3
180°π-100

🎯 What is the Unit Circle?

The Unit Circle is a fundamental concept in trigonometry - a circle with a radius of exactly 1 unit, centered at the origin (0,0) of the coordinate plane.

Key Insights:

  • Every point on the circle represents (cos θ, sin θ)
  • Perfect for visualizing periodic functions
  • Connects geometry with trigonometry

📐 Pythagoras Theorem & Unit Circle

For any point (x, y) on the unit circle:

x² + y² = 1

Since x = cos θ and y = sin θ, we get the fundamental identity:

cos²θ + sin²θ = 1
Unit Circle Equation
x² + y² = 1

📈 Trigonometric Functions

Cosine (cos θ) = x-coordinate

The horizontal distance from the origin

Sine (sin θ) = y-coordinate

The vertical distance from the origin

Tangent (tan θ) = sin θ / cos θ

The slope of the radius line

🎯 Memory Aid - Hand Trick

For Cosine:

3cos(30°) = √3/2
2cos(45°) = √2/2
1cos(60°) = 1/2

For Sine:

1sin(30°) = 1/2
2sin(45°) = √2/2
3sin(60°) = √3/2

Quick Tip:

Count your fingers! For 30°, there are 3 fingers above → cos = √3/2

Remember: Just 3 numbers: 1/2, √2/2, and √3/2

🎮 Interactive Challenge

Can you find an angle where sine and cosine are equal?

Hint: Look for where x = y on the unit circle. Move your mouse over the interactive circle to explore!

Unit Circle Quiz (1/5)

What is cos(0°) on the unit circle?

Unit Circle Quadrants

Quadrant I
0° to 90°
All positive
Quadrant II
90° to 180°
Sin positive
Quadrant III
180° to 270°
Tan positive
Quadrant IV
270° to 360°
Cos positive
🎯
Interactive Learning
Visualize angles and coordinates in real-time
📊
Common Values
Memorize key angles and their trig values
🧮
Dual Units
Switch between degrees and radians
🎮
Practice Quiz
Test your knowledge with interactive questions

Master the Unit Circle - Complete Guide

Understanding the Unit Circle

The unit circle is fundamental to trigonometry because it provides a geometric interpretation of the trigonometric functions. Every point on the unit circle corresponds to an angle measured from the positive x-axis, with coordinates (cos θ, sin θ).

Radians and Degrees

Angles can be measured in degrees (0° to 360°) or radians (0 to 2π). The conversion is simple: 180° = π radians. Our interactive tool lets you switch between both measurement systems to build intuition.

Trigonometric Identities

The unit circle demonstrates key trigonometric identities:

  • Pythagorean Identity: cos²θ + sin²θ = 1
  • Periodicity: Functions repeat every 360° or 2π radians
  • Symmetry: cos(-θ) = cosθ, sin(-θ) = -sinθ

Ready to Master the Unit Circle?

Practice with our interactive tools and become a trigonometry expert!

🔍 Unit Circle Topics & Keywords

Unit CircleTrigonometric FunctionsSine Cosine TangentRadians and DegreesUnit Circle ChartTrig IdentitiesUnit Circle ValuesUnit Circle QuadrantsUnit Circle TableInteractive Unit CircleUnit Circle PracticeUnit Circle QuizUnit Circle CoordinatesUnit Circle AnglesUnit Circle Learning

Values are calculated to 4 decimal places. Perfect for learning and exploration!