22
-
Direction of Vector
An opposite direction of a vector can be easily computed by scaling it with
negative 1 (-1).
Example:
2
Vector A
4
Opposite
Direction
of Vector
A
= -1
2
4
y
=
-2
-4
A
x
-A
-
Dot Product
Dot
product
is
a
procedure of
multiplying two
vectors
and
the
result
is
a
scalar.
The
main
function of
dot product
is
to determine whether the computed vectors
are
orthogonal
(perpendicular)
to
each
other,
which
is
indicated
when
the
result
of dot product is equal to zero.
The formula for dot product is:
u
.
v
=|u| |v| cos ?, where
•
u = first vector
•
v = second vector
•
|u| = length of first vector
•
|v| = length of second vector
•
?
is the angle between two vectors
 |