1 8 CHAPTER 1 • COMPLEX NUMBERS
y
(0, y)
P = (x, y) = z
llm(z}I
!Re(z)I
+----~--1--x
0 = (0, 0) Q = (x, 0)
Figure 1- 7 The moduli of z and its
components.
Figure 1.9 The triangle inequality.
y
(0, y)
- -- - - -~z = (x, y)
/ : =x+iy
- -- - - -~z = (x, y)
Figure 1.8 The geometry of negation
and conjugation.
An important application of Identity (1-22) is its use in establishing the triangle
inequality, which states that the sum of the lengths of two sides of a. triangle is
greater than or equal to the length of the third side. Figure 1.9 illustrates this
inequality.