Geometry: An Interactive Journey to Mastery

Lesson 16: “Circle-ometry”—On Circular Motion

Study Tip

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isosceles triangles and half equilateral triangles.

Pitfall

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values^1122 ,,and 2 3 will eventually stick in your mind, but don’t force this. It never hurts to draw

quick sketches to be sure that what you are half remembering is correct.

1. Find sin 30° and cos 30°.


2. Find sin 150° and cos 150°.


3. Find sin 150° and cos 150°.


4. Find all values of x for which sin x 0.


5. Find all values of x for which cos x 0.

Problems