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← Trigonometry
Semester 1

The Trigonometric Functions

You learn trigonometry from the ground up -- how angles are measured, the unit circle that defines sine and cosine, right-triangle trig, and the graphs of all six functions and their inverses.

Class 1

Angles and their measure

Two ways to measure an angle, and moving between them.

Class 2

The unit circle and the trig functions

The circle that defines sine, cosine and the rest.

Class 3

Right triangle trigonometry

Sine, cosine and tangent as ratios of a triangle's sides.

Class 4

Values of the trig functions

The exact values you should know by heart.

Class 5

Properties of the trig functions

What repeats, and what is symmetric.

Class 6

Graphs of sine and cosine

The waves that describe anything that repeats.

Class 7

Graphs of the other four functions

Tangent and the reciprocals, and their breaks.

Class 8

Sinusoidal graphs: amplitude, period, phase

Stretching and shifting a wave to fit real data.

Class 9

Inverse trig functions

Going from a value back to the angle.

Class 10

More on inverse trig functions

Using the inverse functions together with the direct ones.

Class 11

Modeling with sinusoidal functions

Describing real things that rise and fall.

Class 12

Semester 1 review: the trig functions

Pulling the functions, values and graphs together.