In plane geometry, **angle **is a shape that consists of two rays, which are known as angle edges, which divides a common interval known as the same angle. [1] Who is made by two beams, but this plane should not be a Euclidean plane. Euclidean and other spaces make corners of the intersection of two planes. This is called dihedral angle. Angola which has a portion of the two curves in the plane is defined as the angle determined by the touch ray on the intersection. The same statement is applied in space, for example, the rounded angle of the rounded angle is the rounded between the two circles, which is between planes determined by the great circles.

Angle Angle or rotation is also used to set the rotation size. This ratio is up to the length of the radius of the radius to the radius. In the case of geometric angle, the arc focuses on intrusive and is limited to the edge. During circulation, arc focuses in the center of rotation and is limited by circulation through each other’s point and its image.

The word angle comes from the Latin word angulus, which means “corners”; Cognitive expressions are Greek ἀγκύλος (enclosures), which means “tricky, awkward” and the English word “ankle”. Both are similar to the proto-European root, which means “turn” or “bow”. [2]

Euclid defines an aircraft engagement engulfing each other against each other, two lines that meet each other and are not directly close to each other. According to the Proclus, it is essential to have an angle quality or quantity or relationship. The first concept was used by Eudemus, who thought to be a straight line deviation; Secondly, by the carrier of Antioch, who saw them as a difference or space between distance lines; Although Euclid accepts the third concept, its right, fast and angle definition is definitely bulk. [3]

In mathematical equations, Greek characters (α, β, γ, θ, φ, ...) are often used to serve as vertical variables for some angle size. Latin characters (A, B, C, ...) (To avoid confusion with other meanings, the symbol π is not generally used for this purpose.) But capital letters are used to refer to Roman characters. For example, see the statistics in this article.

In geometric figures, the angle can be identified by the caption at three points which define them. For example, ray AB and AC (D. point B and point-to-mark A, H point A), the vertex at one time lines ∠ bac (unicode U + 2220 ∠ angle) or {\ display style {\ widehat {surrounded by rm} }}}} {\ displaystyle {\ widehat {\ rm {BAC}}}}. Occasionally, if there is no possibility of confusion, who can be nominated only by its peak (“Who”).

Perhaps it was a corner angle, for example ∠ bac can refer to any four angle: clockwise clockwise angle b, angle counterclockwise b, c to cycle angle b or c angle counterclockwise, in which direction of direction of direction of b Does (see positive and negative angles). However, in many geometric situations, it is clear from the context that positive angle of less than 180 degrees or equal is used, and no blur is created. Otherwise, in a conference call counterclockwise direction (positively) angle of angle can be applied so that §BAC always refers to counterclockwise SEB (positive) angle, and refers to C.B on ∠