# Formulas and Tables

Trigonometry# Signs of Trigonometric Functions

Trigonometric functions: \(\sin \alpha, \) \(\cos \alpha ,\) \(\tan \alpha, \) \(\cot \alpha,\) \(\sec \alpha,\) \(\csc \alpha \)

Coordinates of a point on a circle: \(x\), \(y\)

- Four quadrants of the unit circle

The trigonometric circle is divided into \(4\) quarters (quadrants). The first quadrant corresponds to the angle interval \(0^\circ \lt \alpha \lt 90^\circ,\) the second quadrant lies in the interval \(90^\circ \lt \alpha \lt 180^\circ,\) the third quadrant corresponds to the interval \(180^\circ \lt \alpha \lt 270^\circ,\) and the fourth quadrant covers the angles \(270^\circ \lt \alpha \lt 360^\circ.\)

- Signs of the trigonometric functions in the unit circle

### Related Pages

- Definition and Graphs of Trigonometric Functions
- Basic Trigonometric Identities
- Cofunction and Reduction Identities
- Relationships between Trigonometric Functions
- Addition and Subtraction Formulas
- Double and Multiple Angle Formulas
- Half-Angle Formulas
- Sum-to-Product Identities
- Product-to-Sum Identities
- Powers of Trigonometric Functions
- Basic Trigonometric Equations
- Basic Trigonometric Inequalities