Biomedical Engineering Reference
In-Depth Information
Appendix
Some Mathematical Relations Used in This Topic
Geometry
A few examples of supplementary angles are shown in Fig.
A.1
for review:
Theorem If the corresponding sides of two angles are perpendicular to each
other, the angles are equal. In Fig.
A.2
, angle
is formed by sides
a
and
b
.As
side
c
is perpendicular to side
b
and
d
, perpendicular to side
a
, the angle formed by
sides
c
and
d
is also
α
.
Theorem The sum of the interior angles of a triangle equals 180
, as shown in
Fig.
A.3
.
α
Trigonometry
In a right triangle ABC (Fig.
A.4
), the following trigonometric functions are
defined:
opposite side
hypotenuse
¼
a
c
arcsin
a
sin
α ¼
and
α ¼
c
,
adjacent side
hypotenuse
¼
b
c
arccos
b
cos
α ¼
and
α ¼
c
,
α
a
b
,
sin
opposite side
adjacent side
¼
tan
α ¼
α
¼
cos
sin
2
α þ
cos
2
α ¼
1
:
