## RWA Sine, Cosine, Tangent

### Topic

The Earth, Moon and Sun

### Vocabulary

- Sine
- Cosine
- Tangent
- Trigonometric Ratios With a Calculator
- Inverse Trigonometric Ratios

### Student Exploration

#### How did the ancient Greek astronomers determine the size of and distance from the Earth, Moon, and Sun?

Watch the video to learn more:

http://thewatchers.adorraeli.com/2011/09/21/how-can-we-see-the-sun-and-the-moon-at-the-same-time/

### Extension Investigation

Parallax - To Determine Stellar Distances

See how to duplicate their methods

http://www.astro.washington.edu/courses/astro211/CoursePack/cp03a_distance_sun.pdf

Dialate a right Triangle

http://www.ferrismath.com/int1/Sine,%20Cosine%20and%20Tangent.htm

#### Layering (optional)

Trigonometric Parallax

Trigonometry in the real world