The magnitude, or size, of a vector
a\underline{i}+b\underline{j} in 2 dimensions is
found by the formula: \sqrt{(a^2+b^2)}
The magnitude, or size, of a vector a\underline{i}+b\underline{j}+c\underline{k} in 3 dimensions is found by the formula: \sqrt{(a^2+b^2+c^2)}
The magnitude, or size, of a vector a\underline{i}+b\underline{j}+c\underline{k} in 3 dimensions is found by the formula: \sqrt{(a^2+b^2+c^2)}
Summary/Background
The formula for the magnitude of a vector is basically Pythagoras' theorem extended to 3 dimensions.
Software/Applets used on this page
This question appears in the following syllabi:
Syllabus | Module | Section | Topic | Exam Year |
---|---|---|---|---|
AQA A-Level (UK - Pre-2017) | C4 | Vectors | Vector algebra | - |
AQA A2 Maths 2017 | Mechanics | Kinematics | 3D Vectors | - |
AQA AS Maths 2017 | Mechanics | Vectors | Vector Basics | - |
AQA AS/A2 Maths 2017 | Mechanics | Vectors | Vector Basics | - |
CBSE XII (India) | Vectors and 3-D Geometry | Vectors | Types, equal, unit, parallel, collinear | - |
CCEA A-Level (NI) | C4 | Vectors | Vector algebra | - |
CIE A-Level (UK) | P1 | Vectors | Vector algebra | - |
Edexcel A-Level (UK - Pre-2017) | C4 | Vectors | Vector algebra | - |
Edexcel A2 Maths 2017 | Pure Maths | Vectors | 3D Vectors | - |
Edexcel AS Maths 2017 | Pure Maths | Vectors | Vector Basics | - |
Edexcel AS/A2 Maths 2017 | Pure Maths | Vectors | Vector Basics | - |
I.B. Higher Level | 4 | Vectors | Vector algebra | - |
I.B. Standard Level | 4 | Vectors | Vector algebra | - |
Methods (UK) | M4 | Vectors | Vector algebra | - |
OCR A-Level (UK - Pre-2017) | C4 | Vectors | Vector algebra | - |
OCR A2 Maths 2017 | Pure Maths | Vectors | 3D Vectors | - |
OCR AS Maths 2017 | Pure Maths | Vectors | Vector Basics | - |
OCR MEI A2 Maths 2017 | Pure Maths | Vectors | 3D Vectors | - |
OCR MEI AS Maths 2017 | Pure Maths | Vectors | Vector Basics | - |
OCR-MEI A-Level (UK - Pre-2017) | C4 | Vectors | Vector algebra | - |
Pre-Calculus (US) | E1 | Vectors | Vector algebra | - |
Pre-U A-Level (UK) | 6 | Vectors | Vector algebra | - |
Scottish (Highers + Advanced) | HM3 | Vectors | Vector algebra | - |
Scottish Highers | M3 | Vectors | Vector algebra | - |
Universal (all site questions) | V | Vectors | Vector algebra | - |
WJEC A-Level (Wales) | C4 | Vectors | Vector algebra | - |