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 circumference subtends an angle of 2Ï radians. The radian is the standard unit of angular measure, used in many areas of mathematics. The length of an arc of a unit circle is numerically equal to the measurement in radians of the angle that it subtends; one radian is just under 57.3 degrees (expansion at A072097).