What is a vector and how do I calculate the 'modulus' of a vector?

A vector is something that has both magnitude and direction. An example of a vector is velocity because it has magnitude and direction. However, speed is not a vector. This is because it only has magnitude. A vector is represented by OA (with an arrow above it going from the O to the A) or a. In 3-D there are 3 main unit vectors: i, j, k. Where:
i = (1, 0, 0) , j = (0, 1, 0) and k = (0, 0, 1). All 3-D vectors are represented in terms of these three unit vectors. (Unit vectors all have a length of 1). So we can say the general form of a vector, for some vector called a, is: a = x+ yj + zk = (x , y, z) where x, y and z are numbers. Let us try to visualise vector a
In order to find vector a we must move x units in the x (or i) direction, y units in the y (or j) direction and then z units in the z (or k) direction. The magnitude of a vector is known as its modulus (or more simply, length). The modulus of vector a = ( x+ y2 + z2)1/2

AS
Answered by Anya S. Maths tutor

16538 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Why do you times the reciprocal of the second fraction by the first when dividing fractions.


(a) The equation of a line L is 2x-3y=6. Find the gradient of L. (b) Find the equation of the line which is parallel to L and passes through the point (6,9)


(6/x-2)-(2/x+3)=1


Solve the simultaneous equations 5x + 2y = 4 and x - y - 5 =0


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning