Step by step
The question
Question: simplify √48.
1 Find the biggest square number
Square numbers are a number times itself: 2 × 2 = 4, 3 × 3 = 9, and so on.
We list them up to half of 48.
A bigger one can't go in.
We try the biggest first.
Does 16 go into 48?
Yes: 48 divided by 16 is 3.
2 Split the root
So 48 is 16 times 3.
We write it under the root.
Rule: a root over a times can be split into two roots.
So √(16 × 3) is √16 times √3.
√16 is 4, because 4 times 4 is 16.
We write 4 in place of √16.
We leave out the times sign: 4√3 means 4 times √3.
3 has no square number in it, so we are done.
So √48 = 4√3.
3 Check
Let's check: we square the answer.
We must get 48 back.
4 × 4, and √3 × √3 = 3.
We get 48.
So 4√3 is right!
Let's look back.
First: find the biggest square number.
Then: split the root.
Last: check.