The expression for the angle
2−v
differs from
2
by as much as
−v
differs from
0. This means that
2
makes the same angle with the positive
y
-axis as
−v
makes with the positive
x
-axis.
Angle
v
angle
−v
Therefore, the angle
2−v
has a
y
-coordinate which is equal to the
x
-coordinate for the angle
v, i.e.