Surd

Can't remove the square root (unsolvable square root)

A surd is a number that can’t be simplified to remove a square root.

“That’s absurd! (surd) Surely you can remove a square beetroot.” (Square root). But they couldn’t remove it (can’t remove).

Examples

1.   `sqrt2` can’t be removed, therefore `sqrt2` is a surd.

2.   `sqrt4` is equal to 2, so it can be removed, therefore `sqrt4` is not a surd.

Further surds – Always think `sqrt9`

If you see the term surds in an exam you must write out the following.

 Surds - Always think `sqrt9`

Try something you know.

Add

As       `sqrt9+sqrt9=3+3=6`

See if  `sqrt9+sqrt9=2sqrt9` also equals 6

 `=2times3` does equal 6

Therefore `sqrt9+sqrt9=2sqrt9`

Subtraction

 `sqrt9-sqrt9=3-3=0`

Multiplication

 `sqrt9timessqrt9=3times3=9=sqrt81=sqrt(9times9)`

`sqrt9timessqrt9=sqrt(9times9)`

Divide

 `sqrt9/sqrt9=3/3=1=sqrt(9/9)`

`sqrt9/sqrt9=sqrt(9/9)`

 Now you can work out any surd question.