Standard 9: Trigonometry

In grades 9-12, the mathematics curriculum should include the study of trigonometry so that all students can:

• Apply trigonometry to problem situations involving triangles

Benchmarks 9C (The Mathematical World: Shapes)
Grades 9-12, page 225
Distances and angles that are inconvenient to measure directly can be found from measurable distances and angles using scale drawings or formulas.
 

• Explore periodic real-world phenomena using the sine and cosine functions

Benchmarks 11C (Common Themes: Constancy and Change)
Grades 9-12, page 275
In many physical, biological, and social systems, changes in one direction tend to produce opposing (but somewhat delayed) influences, leading to repetitive cycles of behavior.

Benchmarks 11C (Common Themes: Constancy and Change)
Grades 6-8, page 274
Things that change in cycles, such as the seasons or body temperature, can be described by their cycle length or frequency, what the highest and lowest values are, and when they occur. Different cycles range from many thousands of years down to less than a billionth of a second.
 

and so that, in addition, college-intending students can:

Understand the connection between trigonometric and circular functions

Use circular functions to model periodic real-world phenomena

Apply general graphing techniques to trigonometric functions

Solve trigonometric equations and verify trigonometric identities

Understand the connections between trigonometric functions and polar coordinates, complex numbers, and series