In Secondary 4, students are going to learn this chapter 'Vectors'. Some love it, most hate it.

In today post, I'm going to share some basic concepts on Vectors.

**What is a vector? **

A vector is a quantity that has direction and magnitude. Common examples of vector include velocity, acceleration, displacement and force.

The opposite of vector is **scalar**, a quantity that has only magnitude. Examples include time, speed, distance and mass.

As you see, vector is closely associated with physics!

** ****How do we represent a vector? **

Since vector involves magnitude and direction, there will always be an arrow indicting the direction. We call this vector

Vectors can be expressed in a column format called **column vector**. For this example, which means, starting from point A, 3 units to right and 1 unit up. It is similar to our coordinate system 3 units along *x* axis and 1 unit along *y* axis. In general, moving right and up have positive sign while moving left and down have negative sign.

**How to find magnitude of a vector? **

Using the same example,to find magnitude of , we use **Pythagoras's Theorem. **(Refer to diagram above)

Magnitude of can be written as .

I hope you have understood the basic concepts of vectors. In future post, I'm going to write more about the application of vectors.