?
Paul's Online Notes
Home / Algebra / Preliminaries / Radicals
Show All Notes Hide All Notes

Section 1.3 : Radicals

9. Simplify the following expression. Assume that \(y\) is positive.

\[\sqrt {8{y^3}} \]

Show All Steps Hide All Steps

Start Solution

Recall that by simplify we mean we want to put the expression in simplified radical form (which we defined in the notes for this section).

To do this for this expression we’ll need to write the radicand as,

\[8{y^3} = \left( {4{y^2}} \right)\left( {2y} \right)\] Show Step 2

Now that we’ve gotten the radicand rewritten it’s easy to deal with the radical and get the expression in simplified radical form.

\[\sqrt {8{y^3}} = \sqrt {\left( {4{y^2}} \right)\left( {2y} \right)} = \sqrt {4{y^2}} \sqrt {2y} = \require{bbox} \bbox[2pt,border:1px solid black]{{2y\,\,\sqrt {2y} }}\]