Lecture

Trigonometric Circle Basics

Graph Chat

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

Description

This lecture introduces the trigonometric circle as a fundamental tool for the course, explaining its construction, angles measurement, and periodicity. The instructor covers the unit circle, angle measurement in radians, and the concept of periodicity. The lecture also delves into circular motion, describing how to calculate the angles covered by clock hands over time.

Official source

Related concepts (23)

Clock

A clock or chronometer is a device used to measure and indicate time. The clock is one of the oldest human inventions, meeting the need to measure intervals of time shorter than the natural units such as the day, the lunar month, and the year. Devices operating on several physical processes have been used over the millennia. Some predecessors to the modern clock may be considered "clocks" that are based on movement in nature: A sundial shows the time by displaying the position of a shadow on a flat surface.

Trigonometry

Trigonometry () is a branch of mathematics concerned with relationships between angles and ratios of lengths. The field emerged in the Hellenistic world during the 3rd century BC from applications of geometry to astronomical studies. The Greeks focused on the calculation of chords, while mathematicians in India created the earliest-known tables of values for trigonometric ratios (also called trigonometric functions) such as sine. Throughout history, trigonometry has been applied in areas such as geodesy, surveying, celestial mechanics, and navigation.

Radian

The radian, denoted by the symbol rad, is the unit of angle in the International System of Units (SI) and is the standard unit of angular measure used in many areas of mathematics. It is defined such that one radian is the angle subtended at the centre of a circle by an arc that is equal in length to the radius. The unit was formerly an SI supplementary unit and is currently a dimensionless SI derived unit, defined in the SI as 1 rad = 1 and expressed in terms of the SI base unit metre (m) as .

Angle

In Euclidean geometry, an angle is the figure formed by two rays, called the sides of the angle, sharing a common endpoint, called the vertex of the angle. Angles formed by two rays are also known as plane angles as they lie in the plane that contains the rays. Angles are also formed by the intersection of two planes; these are called dihedral angles. Two intersecting curves may also define an angle, which is the angle of the rays lying tangent to the respective curves at their point of intersection.

Pendulum clock

A pendulum clock is a clock that uses a pendulum, a swinging weight, as its timekeeping element. The advantage of a pendulum for timekeeping is that it is an approximate harmonic oscillator: It swings back and forth in a precise time interval dependent on its length, and resists swinging at other rates. From its invention in 1656 by Christiaan Huygens, inspired by Galileo Galilei, until the 1930s, the pendulum clock was the world's most precise timekeeper, accounting for its widespread use.

Related lectures (64)

Angle Measurement: Trigonometric Concepts MOOC: Trigonometric, Logarithmic and Exponential Functions

Explores angle measurement using a unit circle, radians, and trigonometric concepts, including clock hand movements and infinite angles.

Trigonometric Circle: Interpretation and Applications MOOC: Trigonometric, Logarithmic and Exponential Functions

Explores the interpretation of angles on the trigonometric circle and its applications in circular motion.

Circular Trigonometry: Understanding Geometric Angles

Explores the concept of angles in circular trigonometry, emphasizing geometric angles and their properties.

Triangle Resolution: Trigonometric Functions MOOC: Trigonometric, Logarithmic and Exponential Functions

Covers the resolution of triangles using trigonometric functions and the importance of cosine and sine theorems.

Angle Measurement: Radians and Degrees MOOC: Trigonometric, Logarithmic and Exponential Functions