Circumferences they are flat geometric figures usually represented by “perfectly round” figures, but the geometric representation is nothing more than the representation of an algebraic formula.
All geometric figures are defined based on points. Points are objects that have no definition, have no dimension, but represent locations in Analytical Geometry. The straight line, in turn, is a geometric figure represented by a straight and infinite line. However, its definition is given only as a set of points.
similarly, circles they are also defined based on sets of points and their geometric representations are based on these definitions. The definition of a circle is as follows:
Definition of circumference: Circumference is a geometric figure belonging to the plane that is constituted by the set of all points equally distant from a fixed point on that plane.
In other words, given the fixed point O, a point A, belonging to the circle C, has the same distance to What a point B, also belonging to circle C, regardless of what points A and B are.
This distance from point A to point O (or from point B to point O) is called circle radiusand is indicated by the letter a. The point O is the fixed point mentioned in the definition above and is known as center of the circle.
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Center O and points A and B equidistant from point O, that is, the distance from A and B to O is equal to r Title: circumference example
Any line segment that connects two points belonging to a circle is known as rope. The segment that connects two points belonging to the circle and still has its center will be called diameter. In other words, diameter is a string that “passes” through the center of the circumference. Regarding the properties, there are initially two in relation to the diameters: its length is equal to twice the radius and there is no chord greater than one diameter in the same circumference.
Circumference where strings were drawn. One of them is the diameter
In this way, being r the lightning and d the diameter, we can write the following relationship between the radius and the diameter of a circle:
d = 2r
By Luiz Paulo Moreira
Graduated in Mathematics
Would you like to reference this text in a school or academic work? Look:
SILVA, Luiz Paulo Moreira. "What is circumference?"; Brazil School. Available in: https://brasilescola.uol.com.br/o-que-e/matematica/o-que-e-circunferencia.htm. Accessed on June 27, 2021.
