Difference between revisions of "Vector algebra"

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{{Navigation|before=[[Table of contents]]|overview=[[Vector algebra]]|next=[[Unit vectors]]}}
 
{{Navigation|before=[[Table of contents]]|overview=[[Vector algebra]]|next=[[Unit vectors]]}}
 
This article gives a brief explanation of vectors and vector algebra. <br/>
 
This article gives a brief explanation of vectors and vector algebra. <br/>
 +
[File:vectorsopposite.png|right|150px]
 
A scalar value is just a numeric value. In contrast thereto, a vectorial value has a direction. Examples for vectors are all forces and the velocity, which is directed to the driving direction. Vectors are usually denoted with an arrow, for example <math>\vec{\mathbf{a}}</math>. A three-dimensional vector for example is<br/><br/>
 
A scalar value is just a numeric value. In contrast thereto, a vectorial value has a direction. Examples for vectors are all forces and the velocity, which is directed to the driving direction. Vectors are usually denoted with an arrow, for example <math>\vec{\mathbf{a}}</math>. A three-dimensional vector for example is<br/><br/>
 
<math>\vec{\mathbf{a}}=
 
<math>\vec{\mathbf{a}}=

Revision as of 15:21, 14 May 2014

← Back: Table of contents Overview: Vector algebra Next: Unit vectors

This article gives a brief explanation of vectors and vector algebra.
[File:vectorsopposite.png|right|150px] A scalar value is just a numeric value. In contrast thereto, a vectorial value has a direction. Examples for vectors are all forces and the velocity, which is directed to the driving direction. Vectors are usually denoted with an arrow, for example \vec{\mathbf{a}}. A three-dimensional vector for example is

\vec{\mathbf{a}}=
\left[\begin{array}{cccc}
a_x\\
a_y\\
a_z 
\end{array}\right]

where a_x, a_y and a_z describe the components of the vector in x-, y- and z-direction. For graphical representations arrows are used that show the direction of the vector and whose length equals its magnitude. The magnitude of a vector is defined as

|\vec{\mathbf{a}}|=\sqrt{a_x^2+a_y^2+a_z^2}

As the presented notation is comparatively sophisticated |\vec{\mathbf{a}}| is often reduced to a. The vector -\vec{\mathbf{a}} has the same magnitude as \vec{\mathbf{a}} but is directed opposite. Two or more vectors are called equal if they have the same direction and the same magnitude. The zero vector \vec{\mathbf{0}} is a special vector with undefined direction and magnitude zero.

  1. Unit vectors
  2. Simple arithmetic operations
  3. Dot product
  4. Cross product