write radical expression in simplest form

Dec 2013
28
0
the expression is

\(\displaystyle \sqrt{5x^{2}y}\sqrt{3y}\)

these are my steps:

\(\displaystyle \sqrt{15x^{2}y^{2}}

\left |x \right |\left | y \right |\sqrt{15}\)

however in the book the answer is :

\(\displaystyle \left |x \right | y\sqrt{15}\)

why are not the absolute value bars surrounding the y? :help:
 
Last edited:

topsquark

Math Team
May 2013
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The Astral plane
the expression is

\(\displaystyle \sqrt{5x^{2}y}\sqrt{3y}\)

these are my steps:

\(\displaystyle \sqrt{15x^{2}y^{2}}

\left |x \right |\left | y \right |\sqrt{15}\)

however in the book the answer is :

\(\displaystyle \left |x \right | y\sqrt{15}\)

why are not the absolute value bars surrounding the y? :help:
Your original expression contains \(\displaystyle \sqrt{y}\). This means that y has to be positive, so absolute value bars aren't needed.

-Dan
 
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