Math · Intermediate

Trigonometry

Discover why the side ratios of right triangles depend only on the angle. Then extend sine and cosine around the whole circle, measure angles in radians, and unroll the circle into the sine waves found everywhere in nature. Finally, solve any triangle with the laws of sines and cosines, and use them to measure heights, areas and bearings.

10 lessons~60 min0/10 complete

Start courseHelpful background: Geometry: Visual Proofs

1

Right Triangles

Sine, cosine and tangent.

2

The Unit Circle

Angles of any size, measured in radians.

3

Waves and Triangles

Unrolling the circle, and beyond right angles.

4

Triangles in the World

Law of sines, areas, heights and bearings.

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