2 Chapter 1 Introduction to Statistical Quality Control, 5th Edition by Douglas C. Montgomery. 3Copyright (c) 2005 John Wiley & Sons, Inc.Chapter 1 Introduction to Statistical Quality Control, 5th Edition by Douglas C. Montgomery. 4Copyright (c) 2005 John Wiley & Sons, Inc. Learning Objectives.
Notice it always remains an equiangular triangle. The angles A,B and C always remain equal in measure. An equiangular triangle is a triangle where all three interior angles are equal in measure. Because the interior angles of any triangle always add up to 180Â°, each angle is always a third of that, or 60Â° The sides of an equiangular triangle are all the same length (congruent), and so an equiangular triangle is really the same thing as an equilateral triangle. See Equilateral Triangles. Properties
The radian is the standard unit of angular measure, used in many areas of mathematics. An angle 's measurement in radians is numerically equal to the length of a corresponding arc of a unit circle; one radian is just under 57.3 degrees (when the arc length is equal to the radius).he concept of radian measure, as opposed to the degree of an angle, is normally credited to Roger Cotes in 1714. He described the radian in everything but name, and he recognized its naturalness as a unit of angular measure.