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Higher Mathematics. Unit 3.1 Vectors. A. B. 1. Introduction. A vector is a quantity with both magnitude and direction. It can be represented using a direct line segment. This vector is named or or. u. 3. 5. 2. 2. Vectors in 3 - Dimensions. 2. 5. 3. -2. 4. 3. 3. 2.
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Higher Mathematics Unit 3.1 Vectors
A B 1.Introduction A vector is a quantity with both magnitude and direction. It can be represented using a direct line segment This vector is named or or u
3 5 2 2.Vectors in 3 - Dimensions 2 5 3
-2 4 3
3 2 0
3 -3 -2
P (1, 2) Q (6, 3) 3 2 1 6 6 - 1 5 3 - 2 1
S (-2, 1) T (5, 3) 3 1 -2 5 5 - -2 7 3 - 1 2
A (-2, -1) B (4, 1) 1 - 1 -2 4 4 - -2 6 1- - 1 2
4 4 -3 -3 42 + (-3)2
7 1 C B 1 2 -6 4 A D Add vectors “ Nose-to-tail”
v u + v u Add vectors “ Nose-to-tail”
A A -u u B B is the negative of is the negative of
v -v u + -v u u - v -2 -4 Add the negative of the vector “ Nose-to-tail”
-v v The Zero Vector Back to the start. Gone nowhere
2v v 2v has TWICE the MAGNITUDE of v, but v and 2v have the SAME DIRECTION. i.e. They are PARALLEL
P (4, 2) p The position vector is denoted by If P has coordinates (x , y , z) then the components of the position vector of P are 4 2 The position vector of a point P is the vector from the origin O, to P.
NOT collinear E D then the vectors are parallel and have a point in common - namely B - , this makes them collinear B C Collinear A
A unit vector is any vector whose length (magnitude) is one is a unit vector since The vector
-2 4 3 +3 +4 -2 All vectors can be represented using a sum of these unit vectors
The scalar product of the vectors and is defined as: The scalar product (or “dot” product) is a kind of vector “multiplication”. It is quite different from any kind of multiplication we’ve met before. where q is the angle between the vectors, pointing out from the vertex or
Calculating the angle between two vectors We have already seen that Rearranging gives And hence we can find the angle between two vectors
3. Perpendicular vectors: • Provided and are non zero then if then so ie and are perpendiculiar 2. If either or then 4. Some important results using the scalar product • The scalar product is a number not a vector