Building the Unit Circle

Trigonometry · Axiom Academy

INTRO Building the Unit Circle Discover the foundation of trigonometry by exploring how points on a circle relate to angles and coordinates. A unit circle is a circle with radius 1, centered at the origin (0, 0). Click or drag anywhere in the circle to place a point, and watch its coordinates! Drag the point around the circle. Notice how the angle from the positive x-axis relates to the point's coordinates. Some angles have particularly important coordinates that we use all the time in trigonometry. Click on the cards to explore these special angles! The unit circle has beautiful symmetry! Notice how coordinates in different quadrants relate to each other.

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