Baby Vector Math

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Baby Vector Math
An Introduction to vectors By Amy Phillips
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Definition
A vector is defined to be a directed line
segment. It has both direction and magnitude
(distance). It may be named by a bold-faced
lower-case letter or by the two points forming
it - the initial point and the terminal point.
Examples u or AB
B
u
A
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Equal Vectors
Two vectors are equal if they have the same
distance and direction.
u
AB

B
u
A
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Opposite Vectors
Opposite vectors have the same magnitude, but
opposite directions. That is, the terminal point
of one is the initial point of the other.
u
-u
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Resultant Vectors(adding)
When vectors are added or subtracted, the sums or
differences are called resultant vectors.
Geometrically, we add vectors by placing the
initial point of the second vector at the
terminal point of the first vector in a parallel
direction. The resultant vector has the initial
point of vector 1 and the terminal point of the
displaced vector 2.
D
B
A
C
D
AB CD AD
B
C
A
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Resultant Vectors(subtracting)
D
We subtract a vector the algebraic way by adding
the opposite. AB - CD AB (-CD)AD
C
-(CD)
B
-(CD)
A
AD