# "Simple Surd"

• Jul 9th 2006, 11:54 AM
NeF
"Simple Surd"
REally its so simple its difficult

--> Without a calculator simplify $\displaystyle \sqrt18 . \sqrt24$

I get as far as $\displaystyle \sqrt3\sqrt6 . \sqrt4\sqrt6$
$\displaystyle \sqrt3\sqrt6 . 2\sqrt6$

the book says the ans is $\displaystyle 24\sqrt3$
But i have no clue how to achive that answer
• Jul 9th 2006, 12:09 PM
CaptainBlack
Quote:

Originally Posted by NeF
REally its so simple its difficult

--> Without a calculator simplify $\displaystyle \sqrt18 . \sqrt24$

I get as far as $\displaystyle \sqrt3\sqrt6 . \sqrt4\sqrt6$
$\displaystyle \sqrt3\sqrt6 . 2\sqrt6$

the book says the ans is $\displaystyle 24\sqrt3$
But i have no clue how to achive that answer

Since $\displaystyle \sqrt{18} . \sqrt{24} \ne 24\sqrt{3}$ either the book is wrong
or you have copied the question incorrectly.

$\displaystyle \sqrt{18} . \sqrt{24}=\sqrt{2.3.3}.\sqrt{2.2.2.3}=\sqrt{2.2.2. 2.3.3.3}=4.3.\sqrt{3}=12\sqrt{3}$

RonL
• Jul 9th 2006, 12:27 PM
NeF
Hey man thanks alot. The book is wrong x/