The PDF file has four pages to print on both sides of the same sheet with the basic relationships of trigonometry. Use the **worksheets.site** password to open the PDF file. Once the sheet is printed on both sides, it should be folded in half, so you will have a small booklet or book. The PDF file has two pages to print on both sides of a single sheet.

This leaflet will help you solve **trig problems** and make trigonometry homework easier.

- Trigonometric functions in terms of the Other Five
- Common Angles
- Symmetry, Shifts and Periodicity
- Calculus of Trigonometric Function
- Fundamental Properties and Formulas
- Law of Sines
- Law of Cosines
- Law of Tangents
- Pythagorean Identities
- Sum and Difference of Angles
- Angle Sum and Difference Identities
- Product to Sum
- Sum to Product
- Double Angle Trigonometric Identities
- Triple Angle Trigonometric Identities
- Medium Angle Trigonometric Identities
- Power Reduction Formulas
- Difference of Squares to Product
- Composition of Functions
- Sum and Difference of Inverse Trigonometric Functions

In mathematics, the trigonometric functions are functions of an angle, important when studying triangles and modeling periodic phenomena. They are commonly defined as ratios of two sides of a right triangle containing the angle, and can equivalently be defined as the lengths of various line segments from a unit circle.

The trigonometric functions are of great importance in Physics, Astronomy, Cartography, Boating, Telecommunications, the representation of periodic phenomena, and many other applications.

A trigonometric identity is an equality between expressions that contain trigonometric functions and is valid for all the values of the angle in which the functions are defined.