## Trigonometry Trigonometry, abbreviated as TRIG, is a branch of mathematics that deals with the relations between the sides and angles of plane or spherical triangles.

Science
Formal Science
Mathematics
Pure Mathematics
Trigonometry

### Nomenclature & Symbols

• $$arccsc$$  -  arccosecant
• $$arccos$$  -  arccosine
• $$arccot$$  -  arccotangent
• $$arcsec$$  -  arcsecant
• $$arcsin$$  -  arcsine
• $$arctan$$  -  arctangent
• $$csc \;/\; cosec$$  -  cosecant
• $$cos$$  -  cosine
• $$cot \;/\; ctg$$  -  cotangent
• $$sec$$  -  secant
• $$sin$$  - sine
• $$tan$$  -  tangent
• $$TRIG$$  -  trigonometry

## Trigonometry Glossary

### A

• Arccosine  -  arccos, the inverse cosine.
• Arccosecant  -  arccsc, the inverse cosecant.
• Arcsecant  -  arcsec , the inverse secant.
• Arcsine  -  arcsin , the inverse sine.

### C

• Cosecant  -  csc, the ratio of the hypotenuse over opposite side in a right triangle.
• Cosine  -  cos, the ratio of the adjacent side of the hypotenuse in a right triangle.
• Cotangent  -  cot, the ratio of the adjacent side to the oposite in a right triangle.

D

E

F

G

### H

• Heron's formula   -   A formula for the area of a triangle when the lengths of the three sides are known.
• Hyporenuse  -  The side of right triangle opposite the right angle, which is the longest side.

### I

• Infinite  -  Having no boundary.
• Inverse statement   -   Disaliow both the hypohesis and conclusion of the origional statement.

J

K

### L

• Law of cosines  -  An equation relating to cosine of an interior angle and the lengths of the sides of a triangle.
• Law of sines  -  The ratio of the sine of any angle within any specific triangle and the length for the opposite side is a constant.

M

N

### O

• Orthocenter  -  The point of concurrence of the altitudes of the triangle.
• Orthogonal  -  Perpendicular to a plane.

### P

• Pythagorean theorem  -  An equation relating the lengths of the sides of a right triangle.  The sum of the squares of the legs of a right triangle is equal to the square of the hypotenuse.
• Proportional  -  In a constant ratio.

Q

### R

• Ratio  -  A constant proportion or two real numbers divided by each other.

### S

• Secant  -  sec, the ratio of the hypotenuse to the side adjacent to a given angle in a right triangle.
• Sine  -  sin, the ratio of the length of the opposite side to the length of the hypotenuse.

### T

• Tangent  -  The ratio of the opposite side to the adjacent side of a right triangle.
• Tangent line  -  A line that touches the graph of the function at a single point.
• Tangent of a circle  -  A line that contacts an arc or circle at only one point.
• Trig functions  -  sine, cosine, tangent, cosecant, secant, and cotangent

U

V

W

### X

• X-axis  -  The horizontal axis on a coordinate system.

### Y

• Y-axis  -  The vertical axis on a coordinate system.

Z

Display #
Title
Arccosecant
Arccosine
Arccotangent
Arcsecant
Arcsine
Arctangent
Cosecant
Cosine
Cotangent
Law of Cosines
Law of Sines
Secant
Sine
Tangent
Trig Function Abbreviations
Trig Function Equations
Trig Functions