Part 14 - Special feature I | Maths Made Easy

# Surds GCSE Maths Revision

## Part 14 – Special feature I

Square numbers, why are they important?

4,9,16,25,36,49,64,81,100 (hint: it’s a sequence, for more information please refer to “Linear Sequences” tutorial) Because n^2=s and √s=n the square numbers can be taken out of the square root and it becomes simply n.

In other words, from formula m√a×n√b≡=(m×n) √(a×b)≡(mn) √ab if a=s or b=s. Let’s illustrate this with an example:

Example:

Simplify √32

Worked Solution:

Using the rule √ab≡√(a×b)≡ √a×√b and √s=n provided that n2=s, then:

√32=√(16×2)=√16×√2=4√2